In 2001, heads of energy department of G8 gathered in Italy to finalize an important document—the Kyoto Protocol. The biggest news was not the document per se, but the rejection from the US president George W. Bush who promised to cooperate on this issue before 2000 presidential election. As suggested in the memoir by Whitman, the president practically tipped her off.

So what things in Kyoto protocol scared George Bush away? I don’t trust much about news media because they emphasize more on politics than on science. I want to make decisions based on my own research. Therefore, I checked out the Kyoto document itself.

The document is very long but I found two most important items worth commenting.

The first is to define the purpose of the protocol: “The Parties included in Annex I shall, individually or jointly, ensure that their aggregate anthropogenic carbon dioxide equivalent emissions of the greenhouse gases listed in Annex A do not exceed their assigned amounts, calculated pursuant to their quantified emission limitation and reduction commitments inscribed in Annex B and in accordance with the provisions of this Article, with a view to reducing their overall emissions of such gases by at least 5 per cent below 1990 levels in the commitment period 2008 to 2012.” (Emphases were made by myself).

It is clear to me that there was some discussion on how to calculate the assigned amounts. Yes, Montreal protocol did just that. But is the way they calculated the ratification correct? Indeed, George W Bush questioned this as one of reasons for refusing to sign the Protocol. Now NY times reported that there is a meeting going on in England just for this.

Furthermore, who is powerful enough to allocate the ratification? The United Nations? Well, we have seen that the United Nations has little power punishing large countries like the US. If it can’t rule its members, the ability of the United Nations to assign the ratification is questionable.

The number “ 5%” is scary too. To see this, consider the trend of CO₂ emission from 1990-2002 in the US. EPA data estimates that there is a 1% yearly increase of CO₂ emission during that period. To go from the positive to the negative, it is much harder to do than to think. With the expanding economics and the case of California energy crisis in 2001, George W Bush was firmly convinced that a CO₂ emission cut would harm the economic development.

The Second interesting piece in the Kyoto Protocol is the transaction of ratification among countries. “ For the purpose of meeting its commitments under Article 3, any Party included in Annex I may transfer to, or acquire from, any other such Party emission reduction units resulting from projects aimed at reducing anthropogenic emissions…”

In every introductory economics textbook, there is an example on the transaction of air pollutants among members. It assumes that a rationale member will evaluate to the cost of change facilities to reduce pollution compared with that of buying pollution allowance. However, the key is whether there is any punishment for those violates the Protocol. Based on the document, it seems that nothing will happen if you disobey the rule. Ha, no punishment, who cares?

Nevertheless, the Kyoto Protocol is based on its members’ voluntary efforts. The US President George W. Bush has rejected the Kyoto Protocol, partly disputing the scientific evidence of global warming, mostly being pressed by energy industry. In addition, he was also presiding over an economic recession and eager to recover the economics. Under this circumstance, his promise before 2000 election didn’t matter anymore.

One of the US complains was that emerging economic giants — China, India, Brazil and South Africa were not on the list. However, Kyoto members are powerful enough to press the new comers to reduce their emissions in the same way as they have done in the world trade organization. It is irreverent to cite other countries when one was making decision. If you don’t want it, just say so. Don’t shove your responsibility to others.

Do we have ways to reduce the CO₂ emission? Yes, we do. There are several demonstrating projects right now in the United States. For example, the Midwest Twin Cities is advocating adding insulation to residential buildings to save energy. The energy saving plan in municipal buildings has reduced CO­₂ emission by more than 18,000 tons annually. It also saved $160 million per year. Industries are also starting saving energy and reducing their own CO₂ emissions. Green power usage from wind increases. It is doable and the cooler future is reachable.

When I was sitting in the dark waiting for my car warming up last night, my roaming mind suddenly hit a bump. How much carbon dioxide(CO₂) and pollutants did my dearest car emit to the air?

I am not an environmentalist but I do concern about the global warming. In fact, I was once trained in studying environment and health. So when I was skimming through the Nature, a report caught my attention. It says that if we keep on giving off CO₂, the global temperature will raise 2-11⁰C—greater than what we originally thought (2-3⁰C). Incidentally, this week’s Time magazine had an excerpt from the former EPA director Christine Todd Whitman’s book “It’s My Party, too”. In that excerpt, Whitman complained that Mr. President basically tipped her off on the issue of global warming.

Well, politics and science are interesting by themselves, but let’s take global warming personally. Let me introduce my car first. She is sort of an old American beauty and drinks lots of gasoline (and also needs enormous love :-)). It only runs 22 miles per gallon gas but is powerful (V6, 3.1). It never fails me during the winter and always roars through snow piles with one kick. However, after I fumbled through the US EPA website, I was shocked that my precious darling is actually a witch. It has a score of 1 (the worst) in terms of air pollutant emissions. I was somewhat relieved when I found that its score on carbon dioxide (CO₂) is rated as 5 (the average).

As a number cruncher, I figured out that by driving half an hour per day, or 20 miles in the city, my car emits about 5,902 lbs of CO₂per year, less than half of the national average (13,500 lbs). I kept on playing with numbers. The final number for the total emissions by my family came out as a merely 37,100 lbs. Again it is about half of the national average (60,000 for two people). Hmm, not too bad. You can try it by yourself.
(http://yosemite.epa.gov/oar/globalwarming.nsf/content/ResourceCenterToolsGHGCalculator.html)

On the EPA website, there are more numbers. The residential emissions account for about 5.5% of total CO₂ emissions. One third of CO₂ emissions are from energy production, and 27% are from cars and trucks on the road. Overall, the US accounts for 24% of CO₂ emissions of the world (with only 5% population of the world). To make things worse, the US CO₂ emission is increasing at 1% per year from 1999-2002, or about 3.5% increase per year for each person. Among them, the emissions from transportation have the fastest increase. The residential emissions remain stable.

On the other hand, based on the Kyoto Protocol, remaining stable is not enough. We should reduce the emission. EPA suggests that by adjusting the electricity we use in our home, the waste we produce, and the personal transportation, we can reduce 32% of the total emissions per person. Since my guilty is only half of that of average Americans, I don’t know how much improvement I can do. Nevertheless, if there is a will, there is a way.

The first thing coming up to my mind is that I can low the room temperature by one or two degrees. Gosh, the Weather channel predicted that temperature tonight will be about -5⁰F. Looking at my son who wears shorts all the time, I decided to hold my horses till the overall temperature was above 0⁰F. However, before I left home this morning, I did carefully adjust my temperature two degrees more down than usual. I felt good the whole morning.

The second thing is to deal with my electricity. Well, I looked around. I can turn off my computer whenever possible. No TV anytime (which is good). I can also replace unessential light bulbs to lower lumen ones, for example along the stairway. Other utilities? I certainly can’t turn off my refrigerator. All other machines are used only occasionally. Then I remembered that my wife has been yearning for a dishwasher for a long time. I should talk to her right away about giving up that idea. But hold on, I may use other ways to make that buying impossible.

Something about waste has to be done. However, I always recycle my paper and bottles, and have much less trash than our neighbors do. I guess the only thing I can do to reduce waste is to keep all the trash in house.

Till now, all my decisions can save my money although it may not be much. Well, there are two more major things that I can do about. The first is my old car. I have thought of replacing it for a long time. She is still serving me partly because she is doing just fine now and partly because I have had some sort of love-hate feelings for her. Well, I do like you, Dory, but I have to let you go. I am sorry. I quickly estimated that it might cost me more than $20,000 to buy an average new car. This is a big budget.

What about the house itself? I learned that one of my colleagues was installing new insulation onto her house. Well, I also heard that it costs a lot. I don’t know exactly how much but the number can be as much as $10,000. By doing this, I may save some money too from gas bills, but I guess the saving will be far less than $10,000. Anyway, this is a hard decision to make. No rush. I have to let it go too.

After some further musing and pondering, I finally came up a conclusion. The global warming is important, but to make a significant contribution, the costs may be a lot more than the benefits. Because I can’t perceive any immediate benefits, my motivation is also low. Furthermore, there is no punishment if I keep on wasting energy (except for extra $1-2 per months, which are minimal compared with other expenses).

The United States must see the global warming the same way as I do. There is no benefit to reduce CO₂ emissions. In addition, CO₂ is not an air pollutant based on Clear Air Act. Anyway, there are many more important things to do. So the President just plainly rejected the Kyoto Protocol. There is no punishment.

A note: China accounts for about 12.7% world CO₂ emissions, with a 1.3 billion population.

People are inflexible to change their beliefs, and even more stubborn to change their behaviors. Now the Bush administration tries to conquer this hurdle.

Bush advocates abstinence from sex in teenagers to prevent sexually transmitted infections (STIs) which includes HIV infection. Many schools already have sex education. However, the abstinence-only education programs are way too insufficient. Researchers found that those curricula distorted information about the effectiveness of contraceptives and/or misrepresented the risks of abortion. In particular, it blurred religion and science, as it is well known that Bush firmly rejects the abortion idea based on his religious belief.

Furthermore, supporters to “abstinence until marriage” idea believe that teaching young people about “safer sex” is an invitation to have sex. This is ridiculous. CDC has reported that 61% high school seniors have already had sex. For those adolescents whose knowledge is limited to abstinence, they may lack skills to protect themselves when they become sexually active.

Recent FDA decision on plan B pills also reflected this ridiculous idea. Plan B pills can prevent unwanted pregnancy even after sex.Conservative people believe that making Plan B pills over the counter will tout careless sex among young people. They never think about those teenage mothers who have to discontinue their education to raise children. Almost all female headed families are below or close to poverty level. A large percent of them are black women. I don’t think they want to be poor.

Psychologically speaking, people’s beliefs and behaviors can be changed if social norm changes. Bush’s “abstinence from sex” campaign may have some merits on this. However, focusing on abstinence only is insufficient if not misleading.

When I first heard of human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) 20 years ago, I paid no attention to it except fear. I believed that HIV infection was a dirty disease (as many people still believe this even now). The first AIDS case in Shanghai many years ago was a young lady from Yunnan province who was a former illegal drug user and prostitute. During her visit to the department of dermatology in a teaching hospital, she calmly informed the attending nurse that she was an AIDS patient. This caused a panic in the clinic. Although everybody knew what AIDS was, no one knew how to appropriately deal with her. After consulting with the Department of Health, they prescribed some drugs to her and very professionally did some biopsy. After a brief quarantine, the patient took train back to Yunnan. I was fortunate to see the photo of Kapasi sarcoma taken from that lady. Luckily, HIV won’t transmit to other people by taking train together.

Two years ago, a young popular male singer was died of Pneumocystis carinii pneumonia (PCP ????????). It is a typical AIDS pneumonia. Although his attending physician didn’t announce that the singer had AIDS, everybody knew that he had AIDS. This clearly illustrated the stigmatization of HIV infection and AIDS among Chinese. China had let go a good opportunity to educate lay men what HIV infection and AIDS are.

The first wave of research on HIV were mainly carried out in Yunnan and Guanxi provinces, led by Chinese Academic of Preventive Medicine in 1980s. One person told me that they only surveyed those illegal drug users in rehabilitation centers, nothing preventive was done among general population. However, recent studies started to look at prostitution in China.

In a 2001 survey, 95% businessmen and traders confessed that they had at least one commercial sex recently. Among more than 120 million migrating workers (the “floating population”) who live under stress, most migrating men are also sexually deprived. This will lead them to seek a temporal relief from prostitutes, but most of them have no knowledge of safe sex. Relevant data were unavailable. Nevertheless, an HIV infection chain from prostitutes—workers—wives—children may lead to an epidemic in rural areas where public health services are almost none.

Women may be three times more likely to contract HIV infection due to their anatomically receptive nature. Therefore, prostitutes unwillingly become HIV reservoirs. The prevalence of HIV infection among prostitutes in China was about 2% based on rehabilitation center data, but may be underestimated. More than 80% of them didn’t know condom can protect HIV infection.Till now, safe sex education targeting prostitutes are limited because prostitutes are invisible in most people’s eyes. Consequently, the government adopts the strategy “out of sight, out of question”. Chinese government should face the reality and advocate the “100% condom usage among prostitutes” campaign as Thailand has successfully implemented.

The next example is the saddest and widely known, but I recorded here to remember these poor people. In Henan province, many rural peasants contracted HIV when selling their plasma, a procedure involving transferring blood back after plasma were extracted from blood. The bloods were usually pooled with bloods from other people. Syringes were also shared among them. Official data reported that more than 25,000 peasants were HIV infected. Many scholars thought the total blood transfusion related cases could be a million in China. The blowout of this tragedy in 2002 struck the whole world and eventually forced Chinese government to take HIV seriously.

In the above example, those peasants have nothing to be blamed. It is the poverty and the social insecurity that drove them to sell their bloods. This should not happen again.

A striking statistic: by 2003, 840,000 HIV carriers, including 80,000 AIDS patients in China.

I once spoke to a student who went to Africa (forgot the country name, I think it’s Kenya) as a peacecorp member. Her main responsibility was to educate your women about the risks and prevention of HIV infection. She was surprised that those religious people attributed the plague of HIV infection to the God. They kept on asking the question: “Is HIV infection the God’s intention to punish us?” They believed that they didn’t do anything wrong. But why this happened to them?

It is indeed true that most HIV infected African women didn’t do anything wrong. They were the victims of their husbands’ sin. In most developing countries, men worked in cities to make a living where their sex behaviors were unrestrained. The occasional retreats gave their wives and their children disasters—HIV infection.

Well, blaming the God may be a blasphemy. Then whom else can one blame? A recent study conducted by Rand Corp and Oregon State U revealed that among African American in the US, a large number of them believed that it was the government scientists who spread the HIV among them. However, this didn’t surprise me. The conspiracy theory of HIV has lingered in the black population for a long time. This data just confirmed it.

Although this seemed absurd, the conspiracy theory significantly hindered the distribution of government help. The beliefs that drug companies are using them as guinea pigs to test new drugs and the government is reluctant to help them result in hostility among those with HIV infection. Everybody can guess the consequences from this hostility.

Fortunately, most of us are not so blinded to science. We know that HIV somehow jumped from monkeys to human beings more than 20 years ago. One can contract HIV infection mainly by having unsafe sex with HIV carriers, by transfusing contaminated blood products, or by sharing syringes during illegal drug uses. Mothers can also transmit HIV to their children (vertical transmission). It may take years from HIV infection to AIDS. There are three types of drugs now which can control virus replications and bring back CD4 cells–T helper cells in our immune system. The vaccine development is also on the way. We should remain optimistic that in the near future, we will conquer this disease.

A couple days ago, Charlie Bell, the former McDonald’s CEO, died of colorectal cancer at the age of 44. About a year ago, the CEO before him died of heart attack at the age of 60. Many people keenly pointed out that it is McDonald’s hamburgers that killed them. Well, maybe. The free meals that all McDonald’s employees enjoy during the work are fat loaded fast foods. They are not healthy foods. We all know that. But how bad the McDonald’s fatty foods are?

Today I took my family to the infamous McDonald’s simply because both my wife and I didn’t want to cook the lunch. I ordered a Big Mac (without French fries) and my son ordered a chicken nugget Happy Meal. My wife, a health-conscious person, ordered a salad. It was a quite joyful meal and everybody felt stuffed. Out of my professional curiosity, before I walked out of the McDonald’s, I started wondering how much bad stuff I had eaten today. I looked around and discovered some nutrition brochures just right beside the door. I have to admit that I never noticed them before. Well, it wouldn’t hurt me if I grabbed a few brochures.

The McDonald’s nutrition fact booklet looks very professional. There is a huge table similar to the nutrition labels required by FDA. The table lists major nutrients for all foods McDonald’s currently serves. In this big messy table, I quickly located the line for my Big Mac. A Big Mac weights about 219 grams and has 560 kcal. Well, it sounds just fine for my 2000 kcal daily allowance. The next column shows that 270 kcal are from fat in the Big Mac (total fat: 30 grams, half of my daily allowance, FYI, the DV% column, daily value, tells how much your daily allowance has been spent by eating this meal.). Hmmm, 50% seems too much.

I moved my fingers to the next column which is the bad fat–saturated fat. It is about 10 grams, again accounting for half of my daily allowance (total allowance 20 grams). Gee, after gobbling down some tasteless beef patties and low grade cheeses, all of a sudden I had lost half of my bad stuff allowance. This created some internal conflicts when I was trying to enjoy some delicious pork chunks during the dinner.

The next column is a very interesting one. Trans-fats are about 1.5 grams in a Big Mac. Although 1.5 grams don’t seem a lot, my daily allowance for trans-fats is 0, as the new dietary guideline almost prohibits eating trans-fats. I quickly searched down the trans-fat column to see which food has the largest amount of trans-fats. Not surprisingly, it is the large French Fries: 6 grams of trans-fats per serving! Thank goodness, I was lucky leaving French fries out of my order (because I knew it before. :-)).
I asked my wife whether she knew the differences among saturated, unsaturated, and trans-fats. She looked somewhat embarrassed. She admitted that she knew something about saturated and unsaturated fats. But the “trans-fats” was a new word for her. This was not surprising. Her biochemistry knowledge was pretty rusty after so many years of not mentioning the word “biochemistry”.

Well, I haven’t done any lab work for years either. To be more scientifically learned, I decided to entertain my wife and myself with the joy of sharing knowledge. I grabbed my old medical biochemistry textbook only to be disappointed that there was no mention of trans-fats at all. My not-so-old nutrition textbook didn’t help me much either. Nevertheless, Google is always available to satisfy my curiosity.

Fatty acid is essentially a long chain of carbon atoms attached with lots of hydrogen atoms. In saturated fat, every carbon atom binds two hydrogen atoms (except at ends). In unsaturated fat, a couple carbon atoms have only one hydrogen atom, thus creating a double bond between two neighboring carbon atoms, i.e., unsaturated. There are monounsaturated or polyunsaturated fatty acids depending on the number of double bonds. Naturally, the two neighboring hydrogen atoms in these unsaturated sites stay at the same side of carbon chain, i.e., cis alignment. These unsaturated sites can be saturated by hydrogenation– adding hydrogen atoms onto carbon atoms. Most unsaturated fats (for example vegetable oils) are liquids and easily oxidized (when oil has disgusting smells, it is oxidized). Food industry commonly uses partial hydrogenation to create half-liquid half-solid fats. For some reasons, the two nicely aligned hydrogen atoms along the double-bonds sometimes move to opposite side, make a trans (opposite) alignment.

Recent knowledge suggests that trans-fats are as bad as saturated fats. Studies found that trans-fats can increase the risk of heart disease. Unfortunately, one study estimated that 2.6% of our total energy intake was from trans-fats. Cakes, cracks, animal products, margarines, shortening, and fried potatoes contain high trans-fat. Gosh, by saying this, I realized that I might have to throw away a pack of preserved cheese, a big bottle of shortening, two boxes of Oreos, and some of my son’s favorite cracks.

I once talked to someone who proposed labeling trans-fats. There were indeed some struggles between academics and industry. At the beginning, the food industry was very angered by this discovery. They complained that labeling trans-fats might confuse customers. For example, we used to recommend margarine over butter as healthy foods. Now we are saying what we said before is not 100% correct. In addition, the facility adjustment can also cost food industry a significant amount of money about which they care the most. Nevertheless, FDA recommended adding trans-fat content to food labels in July 2003.

Trans-fats are bad, but there is more bad stuff. The next column in the McDonald’s nutrition table is cholesterol. How much cholesterol does a McDonald’s Big Mac have? 80 mg, about one fourth of my daily allowance (300mg). My goal is to reduce cholesterol intake to a minimal level (say less than 300mg according to the dietary guideline). As a matter of fact, our human body can make cholesterol from carbohydrates in the liver. A high load of cholesterol in body can lead to atherosclerosis, in which arteries are fattened by the excessive deposit of cholesterol esters in blood vessel cells. The blood vessels may be blocked by the disruption of plaques. These plaques are the consequences of repeated inflammation within endothelium. If the blockage happens in heart vessels, it creates a heart attack; if it happens in brain, it creates a stroke.

Furthermore, human body only needs seven nutritionally essential fatty acids which our human body can’t synthesize. All these essential fatty acids are unsaturated fatty acids. DHA and EPA are among them. On the other hand, those saturated fatty acids can be synthesized within human body, for example, by liver cells. So they are not essential. People can live with very little saturated fat intake, as monks have practiced for thousands of years.

The take home message is this: vegetable oils and fish oils have a large amount of unsaturated fatty acids, while animal oils have lots of saturated fats. The new guideline further informs us that processed foods and oils are bad for you too because of trans-fats.

Another related message is a rule of thumb for your own benefit: the total cholesterol should be below 200 mg/dL; the low density lipoprotein (LDL), below 100 mg/dL; fasting triglyceride levels, below 150 mg/dL; and the high density lipoprotein (HDL), the good lipoprotein, ABOVE 40 mg/dL. I assume you have heard of these terms before.

There is other bad stuff in a Big Mac such as high sodium content. But I will leave it for my future post when talking about sodium, potassium, calcium, hypertension and the role of kidney in our body.

Modern human beings are fond of adding weight to their ugly bodies to such an extent that many have to turn aside to get into their bedrooms. Other than genes, which approximately accounts for 30~ 60% of obesity and which we can do nothing about, poor diet and sedentary lifestyle are likely the culprits. To prevent obesity and associated consequences, we should address our modifiable lifestyles.

Recently, the Center for Disease Control and Prevention (CDC) bravely addressed this question: “how many deaths are attributed to our lifestyles?” The paper published in JAMA in March, 2004 drew a great deal of interests from many groups including the US Department of Health and the Congress. Unfortunately, the attributed death number due to poor diet and physical inactivity was wrong. This mistake provoked widespread discussions in both mass media and academia.

People often publish wrong results due to typos, miscalculations, or even wrong models. Randomly opening a scientific journal, you will see a section called “errata” at the end of the journal in almost all issues. CDC also made mistakes in its publications before. Why did things get so “violent” this time?

The main reason is that this paper was supposed to be very important in public health. It was written by a government agency, and the authors were high rank directors in the CDC. Future health policies and funding opportunities would be significantly affected by papers like this one. For example, just right after the appearance of this paper, the Robert Wood Johnson Foundation issued memos about cutting back tobacco funding while increasing obesity related intervention funding. The Secretary of Health and Human Services Tommy Thompson also cited this paper in his public speech. The importance of this paper is enormous.

So what was the mistake the authors had made in that paper? Well, the mistake is not easily detectable if you don’t read it carefully. I will try my best to explain their methods at the end of this essay. But if you are not interested in the methodological issues, here is a brief description of key problems in that paper.

In that paper, the authors used different formula to compute attributed deaths for tobacco and for poor diet/physical inactivity. Furthermore, they didn’t account for sex, age, smoking, and other factors when computing the attributed deaths for poor diet/physical activity. Some assumptions were unfounded, but they used them liberally.

These and other neglects were instantly caught by some keen readers. In fact, the accompanied editorial also noticed the methodological inconsistency in that paper but thought it was OK. Among many letters to editor, two letters correctly pointed out the methodological flaws which I also detailed at the end of this essay. The healthy scientific skeptics, however, lead to something bigger than science.

People working on tobacco research first opened fire on this paper. They not only questioned the scientific merits of this paper but also suspected conspiracies behind the paper. They argued that it was unbelievable that this paper was passed through the internal review in CDC. Furthermore, within the CDC, there were some debates on related methodological issues. Two papers from the author’s division suggested that traditional methods (the same method used in the JAMA paper) might overestimate attributable deaths.

Quickly, mass media heated the debate. By the end of November last year, all major newspapers reported this incidence. For example, In a Wall Street Journal interview with Dr. Julie Gerberding, the director of Chronic National Center for Chronic Disease Prevention and Health Promotion, who was also one of the authors in the JAMA paper, Dr. Gerberding acknowledged the problem and stated that they had initiated internal investigation right after they received concerns from readers. She assured the reporter that there was no misconduct in the paper and claimed that scientific integrity was important in research. However, her comment– “This paper in and of itself is a very minor contributor to our knowledge of obesity”, is a sure sign of discrediting that important paper.

This week, the authors finally gave a letter of correction in JAMA stating that due to errors in computation, “(formula) modifications were not copied properly from the first to the next 5 spreadsheet tables.” The final attributed deaths for poor diet and physical inactivity were 365,000, about 35,000 less deaths than that in the original report.

The corrected number is not important now because nobody will cite that paper any more. Damages were done. There will sure be more internal debate within CDC and academia. However, the scientific integrity and political involvement are again in question. Let’s wait and see.

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Appendix: methodological issues in CDC JAMA paper.
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To compute the deaths attributed to risk factors such as tobacco and poor diet, you first need attributable fraction (or attributable risk ratio) for any specific risk factor. In that paper, the attributable ratios were obtained from several studies, and then the ratios were weighted by the percent of people engaging that risky behavior to get an overall attributable fraction. Because many risk behaviors have several levels, e.g., never smoked, former smoker, or occasional smokers, or heavier smokers, the weighting strategy is reasonable. The attributable fraction was then applied to the vital statistics–which is conveniently available in CDC, to obtain the attributed deaths. However, the key problem here is where you get the original attributable ratios. Another problem is whether the attributable ratio is adjusted (or controlled) for other factors such as sex and age.

The dispute was centered on the different methods used in computing tobacco attributed deaths and diet and physical activity attributed deaths. In computing tobacco related deaths, the authors used well established attributable ratios from other studies, and the tobacco use prevalences from Behavioral Risk Factor Surveillance Study (BRFSS). The computation was stratified by sex and age.

In computing deaths related to poor diet and physical inactivity, the author took an indirect approach. They used attributed ratios for obesity (and also data) from a study done by Allison DB et al., in which raw data from six studies were pooled. They argued that poor diet and physical inactivity accounts most of the hazardous effects of obesity, which is probably true. However, the attributable ratios were computed differently from those for tobacco. The obesity attributable ratios were marginal ratios adjusted for sex and age, and the authors used these ratios directly on the whole population instead of stratifying by sex and age, as what they did in the tobacco computation. People argued that obesity is less harzardous with the increase of age. The way the authors did was incorrect.

Furthermore, the authors thought (correctly) that poor diet and physical inactivity had other detrimental effects on health besides obesity. For example, poor diet is related to high cholesterol, and physical inactivity may be related to worse cardiovascular fitness. Therefore, the authors added 15,000 deaths in additional to those from obesity alone. However, they didn’t give any references on how they got this magic number.

My impression is that although the authors may overestimate the obesity related deaths, they may actually underestimate deaths from poor diet and physical inactivity because poor diet and physical inactivity can directly and significantly increase the risk of cardiavascular diseases and cancer, which are top 3 causes of death. In a previous report done by other investigators which answered similar questions, they directly examined the poor diet and physical inactivity. Their method was valid.

Fat guys, good news (or is it a bad news?), the 2005 US dietary guideline was just out (http://www.healthrus.gov). Your never-reached goal has been pushed to an even higher level. Go get depressed. Hey those Atkin dieters, go jump out of window right now. The new dietary guideline is not for you.

The new guideline indeed troubles me quite a lot. Not surprisingly, the new dietary guideline advocates more fruits and vegetables in our daily diet than the old ones did. It used to be “FIVE A DAY” (which was from National Cancer Institute campaign some years ago). Now it is “NINE A DAY” – “Four and one-half cups (nine servings) of fruits and vegetables are recommended daily for the reference 2,000-calorie level, with higher or lower amounts depending on the caloric level.”

Gosh, there must be some conspiracies between the US dietary advisory board and the grocery store association. I always see “FIVE A DAY” sign attached to the gorgeous and overpriced vegetables in my local grocery stores. Now I can foresee that there will be a big new sign “NINE A DAY” attached to every vegetable. I am thinking about opening a small grocery store at the corner of my health conscious community.

The new guideline also emphasizes an increase of whole grain intake. Hmm, I looked down the whole grain list trying to find my favorite grain—white rice. My God, there is no mention of white rice at all. I fully understand that white rice is highly processed, and lots of nutrients (especially vitamin Bs) are lost during the process. But it is still the main sources for nutrients and energy among most eastern Asian people. It seems to me that my little son’s hunch is right. White rice is not good for you; switch to something healthy, such as oatmeal or popcorn. The whole grain breads sometimes look gross to me, and they are tough to my stomach. Is that stuff we used to feed pigs in rural China?

Anatomically, a grain consists a bran (or fiber-rich outer layer), an endosperm (middle part), and a small part called germ (the nutrient-rich inner part). The claimed nutrients will be preserved if you use whole grain to make foods. It is interesting that after controlling for fiber, other vegetable intakes, and physical exercise, many studies showed that the whole grain intake was still significantly positive in predicting good health. Is there something magic in whole grains? Nutrition biochemistry is working on it frantically. However, I think it is still the fiber that does the magic, not the variety of nutrients. All those nutrients are readily available in meats and other vegetables which taste much better than whole grain breads. In addition, those who eat a lot of whole grains are health-conscious people. They will stay healthy no matter what.

It is of note that this new guideline explicitly talks about trans-fatty acids. Fried oils (even using vegetable oils) will produce trans-fatty acids. We Chinese always heat oil to a very high temperature (300F above) during cooking. Should I persuade my wife to add oil after foods are cooked? What a revolutionary idea!

The new guideline also warns people that in addition to take skim or reduced fat milk (a lot of milk, two or three cups a day) they should reduce fat products such as fat loaded cheese and yogurt. This is good. Sometimes it is disturbing to see those sophisticated chefs in the FoodNetwork keep on bragging about delicious cheeses. Fire them.

I also have some concerns about nuts and legumes. I saw an advertisement recently saying that eating peanuts are good for you. Well, it does add antioxidants to your body, thus protecting you by reducing oxidative stress. What about extra-energy you are taking?

Anyway, I have no trouble eating vegetables because most Chinese cuisine is largely vegetable based. I am disappointed that the new dietary guideline doesn’t give specific instructions on how we should cook these foods. It seems to me that they are advocating eating these vegetables in raw form. I just can’t bear it. Eating raw foods is so uncivilized.

It is true that many people can somewhat change their diet. However, there is one big challenge that fat people fear most and find hopelessly unattainable. Physical activity is up to a higher standard than before—workout for 60-90 minutes DAILY. Please note that the new guideline increases not only the duration of exercise (from at least half an hour to more than an hour) but also the frequency (from three times a week to most days). The usual 30 minutes plan is only suitable for preventing chronic disease (translation, sick prone people, elderly). “For most people, greater health benefits can be obtained by engaging in physical activity of more vigorous intensity or longer duration”. Think about this, 65% American population will have to spare one hour per day jogging, biking, and all sorts of weird activities. It is really a big project for American.

Needless to say, physical activity can improve your cardiopulmonary fitness and immune system. Here is one small tip for you. When you feel mindless, stressful, or even angry, you just go out and run around your house, sweating, panting, being completely exhausted, and then you will feel great.

Unfortunately, in one survey, one fourth of American population reported that they didn’t do any physical activity at all during last month before survey. This excludes me because I just did a vigorous physical activity the day before yesterday, but it is the only one during last month. I don’t know how I can make a plan for a 60 min daily exercise, let alone implement it. To be honest, I never had a plan to do a 30 min daily exercise. I am dismayed and desperately watching my tummy growing bigger and bigger.

Obesity is pandemic. But I am not going to worry about it. As a matter of fact, most overweight people live just as happily as the thinners do. People are also living longer and healthier than before. And remember, about 65% Americans are overweight or obese. I feel comfortable hanging around with fat people because comparing with them, my tummy is barely noticeable. Maybe one day a little fat will be considered attractive. Who knows?

Want to evaluate yourself? Here is the way to compute your body mass index (BMI): weight(kg)/height2(meter), less than 25, you are in good shape; 25-29, overweight; 30-34, obese; 35+, severe obese; 40+ morbid obese. However, if your BMI is less than 18.5, please take this caution: you are at the same risk as those obese people. Please eat more.

Please also consider another obesity measurement the dietary guideline left out: the waist circumference. Waist is more important than BMI in terms health risk. How big is your waist? For men, 102+ cm is considered central obesity, and for women, 88+ cm.

News of the death of Mr. Zhao Zi Yang, the former General Secretary of Chinese Communist Party, spread over the Internet. He was famous because he was forced to step down after Tiananmen Square crackdown in 1989. I have no intention to discuss causes and consequences of that event, neither do I have any judgments on it. However, some theoretical analyses in terms of revolution do deserve some attentions. What I mean by “revolution” here is not judgmental, as a revolution can be anything.

Frustration theory is one of many theories which can partially explain the rise of revolution. It suggests that the confliction between the government (and associated dominators) and those dominated will get tenser over time, thus provoking a revolution. For example, in the Marxism, a revolution is caused by the confliction between working class and capitalists. However, this was not the case for the revolution at the beginning of 1900s in China, neither was the case for the 1989 event. To see this, before 1989, the great confliction was between those rich and those poor due to increasing income inequality. But it was the students who first stood up. The target of its fight was the corruption of the government.

One may notice that during the 1980s, the fast economical growth benefited the whole population. People were enjoying an open political atmosphere which one could not imagine 10 years ago. If life was getting better, why was there a revolution? Mr. Deng Xiao Ping didn’t foresee this during 1980s, even after the earlier sign of revolution such as 1986 UTSC event. One theory suggests that it is not the actual worsening condition but the widening gap of expectation and reality that provokes a revolution. The better condition you have, the higher expectation you may ask for. Furthermore, even though people are getting richer and more freedom, this friendliness of the political atmosphere acts like an invitation for those dissenters to fight. It encourages them to seize this opportunity to overthrow the government. In this sense, the Marxism revolution theory is plainly wrong.

Now here is another piece to consider. To succeed a revolution, one key element is to question the legitimacy of a government. Who can question the legitimacy of the government and who wants to question it? Obviously those know the government well. The reasonable candidates are intellectual groups.

Furthermore, those who want a revolution are those who can benefit from it. They are power hunters. This is the basic idea of power theory. The hunters’ interests are different from those of general population. They need the general population because they need followers and enough people to fight against government. This theory may sound astonishing at first, as Mr. Mao Ze Dong had claimed that “revolutionists can’t part with the general population just as the fish can not live without water.” Think carefully, this says that revolutionists need the general population to work for their purpose. It doesn’t take consideration of general population’s interests. History already told us, every successful revolution finally fell into the hand of intellectuals. In other words, the intellectuals were the leaders of revolution, not the general population.

Now looking at the later 1980s in China, it is clear that the intellectual groups deeply involved in planning this event. However, there was no one good enough and ambitious enough to lead the revolution. From the very beginning, it would fail. During the events, it constantly changed their focus; it never seriously questioned the legitimacy of the government except at the later stage. They lacked intellectual support from the majority of intellectual society. Furthermore, nobody knew what kind of benefits would be from the success of the revolution. Although they did motivate part of the general population, the lay men were of no use. To some extent, the general population were just free-riders. The post-event ruthlessness of the general population further testified this conclusion.

Retrospectively, is that event preventable? I don’t think so. With an open political atmosphere and peer pressure from eastern European countries, facilitated by the western society, the event would come without the death of Mr. Hu Yao Bang. Indeed, even before Hu’s death, people already gathered to plan something during the congress meeting.

Mr. Deng summarized nicely after the event: “the biggest mistake in 10 years renovation is the neglect of ideology.” With a tight control of intellectuals these days, the society is still stable despite the existence of much greater income inequality than before.

Chairman Mao was indeed wiser than Mr. Deng.

When two people decide to get marriage, both of them certainly envision a bright future. Thank God, most families start this way. They may think they love each other so deeply that they will go through life together, no matter whether life will be hard or good. Unfortunately, half of them will get divorced in a couple years. It’s just a plain fact.

What’s wrong with the marriage in modern society? Haven’t all modern young people thought carefully about family life before marriage? Is marriage itself detrimental to something? Well just like the old saying: “marriage is the tomb of love”. Without love, marriage won’t last long.

Marriage consists of two people interacting on a daily basis. It is reasonable that a good start to dissect the marriage is to examine people, ourselves.

“Know yourself”, requested the Greek Philosopher Socrates. Socrates didn’t have a modest wife. But his question is still relevant. The question “Who am I?” is so intrigue that many people get depressed when confronted with this question. As a matter of fact, people in severe depression get so absorbed into this question that self-denying causes him/her suicide. It is such a serious question that most of us don’t dare to ask ourselves this question very often. Incidentally, people generally think low of their worth of life, the self-esteem.

No matter what self-perception you may have, most of us will think we are smart enough to explain and predict our behavior. We always hear these types of assertions: “I know what to do. My gut tells me what to do. I will be responsible to the consequences”. Retrospectively, we also think what we have done is alright, responsible, and worthwhile. Is this true?

Unfortunately, our intuitions are often dead wrong about what we will feel and do. Take the marriage as an example again. People in love are primary focusing on the positives and playing down the hardship of future life. They think their love will last for ever. Needless to say, for quite a lot loves, they fade away before marriage. For those loves which do bring to a culmination, half of them will end after marriage. Statistically speaking, the predictability of our gut is way too low.

Furthermore, the unrealistic optimism, exemplified in marriage situation, make all young couple feel confident that their loves last for ever. When commenting other people’s marriage failure, we always say: “those guys have problems themselves. We are different from others. We are better than them.” It sounds like a joke: “everybody is better than average.” It simply overestimates the future.

Ironically, most people attribute their marriage failure to their partners. They downplay their wrong doings (if any), and emphasize that their wives are mindless, bad tempered, tasteless, or their husbands are disgusting, unfaithful, careless, lazy, so on and so forth. This is the self serving bias all human beings have.

Let’s leave this arresting reality for a moment and examine the so called happy marriage in which marriage do last to the end of life. Naïve people may believe that for a marriage with love, caring and sharing are the most important. Sadly reality is too murky and full of sin. One national survey have shown that 91% of wives and only 76% husbands credit wife did most of the grocery shopping. And husbands always underestimate the proportion of housework wives have done. Do you think there is no daily confliction in these families? Self serving bias is everywhere.

There are more to say about self. Here I give another example of our ignorance of ourselves, but for good purpose. When facing tragedies, people feel tremendous sorrow and think they will never recover. Well, most of us do recover, and quite some can do it in just a very short time. For a simple example, when two dating people break up, one of them may feel deeply hurt. However, most people get a fresh restart within a year. Survivors from disaster such as earthquakes or tsunami quickly recovered even though their relatives may die in the disaster. Evolution of self works pretty well in these situation.

Self-analysis is of no use, to some extent. Even if we do rationalize our behavior before we implement it, our actually behavior may still differ from what we have planned, and the consequence of our behavior are as unpredictable as those unplanned behavior. Our self-report is inaccurate. It is possible that our mental process of thinking itself may be different from the mental process of results. We may don’t know why we behave the way we do. We human beings are hopeless. Period.