Time discounting is an economic concept which can be illustrated in this simple question: would you rather get $1 now than get $1 next year? Most of us will choose to get $1 now because $1 next year is worth less than $1 today, assuming there is no inflation. This is time discounting. Everything in future is worth less than things now (except for wines and antiques, for sure).

The financial interpretation of time discounting can be generalized to other dimensions. For example, one year of life now is worth more than one year of life ten years after, even after you take account of aging effect. Time discounting is an important parameter in calculating quality of life measurement.
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Many weight loss books start with a chapter listing all the benefits of weight loss. I prefer a different approach. I believe that most heavy people understand that weight loss is a good thing to do, and some may have tried several weight loss programs, but needless to say, all failed.

You may be curious and anxious to know why you failed the weight loss programs. This is a fine question, but I will not answer it, as I am not interested in any fad diets or exotic exercise programs. I am a scientifically trained researcher and have spent a couple years examining body weight, exercise and nutrition in a large multicenter study. Years of training in medicine and research methodology preclude me from believing any claims that are not supported by rigorous research.
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In 1981, CDC received reports from Los Angles of five cases who had rare Kaposi carcinoma and severe immune suppression. These cases were thoroughly investigated because the disease clustered in a unique population—among those men who had sex with men. The initial interest was to examine whether the unusual sexual behavior was linked to this disease. It was suspected that a new infectious disease occurred. The virus was identified in 1986 by researchers in France and the US. Human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) have become common words since then.

Where did HIV come from? Any curious mind would ask but no one is able to answer. Most scholars now agree that this deadly virus was originated in Africa, presumably from the chimpanzees living in Cameron or Congo.
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For anybody who is losing weight aggressively, there is always a problem lingering in his/her mind. Could something go wrong if the weight loss goes too fast?

This is a legitimate question. Besides exercise injuries and minor side effects of low calorie diet such as diarrhea and heart burn, there is another complication which is less common but also real. Studies have consistently found that those who lose weight rapidly using extreme low calorie diet may be in a higher risk of developing gallbladder stones. In a pooled analysis of several small weight loss programs, the authors found that weight loss is related to the risk of developing gallbladder stones in an exponential curve fashion with the threshold at 1.5 kg per week (3.3 pounds per week). The incident rate is 5 per 1,000 at 1.5 kg weight loss per week, while it is about 1.7 per 1,000 at 2 kg (4.4 pounds) per week, a triple increase of risk. It seems I am lucky that I hadn’t had symptomatic gallbladder stones during my aggressive weight loss. Thank goodness!
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Last Sunday, when I stood on the scale, I was shocked to discover that I had gained four pounds during the Thanksgiving holiday. Gaining a little weight during the holiday was expected because I had indulged myself in delicious foods and laziness, but I didn’t expect to gain so much weight. How could that happen?

It is true that not all weight I had put on is fat. A large part of them must be water. Nevertheless, studies have shown that when regaining weight, the body is more likely to deposit fat than lean mass, especially during the fast weight regain. It is possibly because fat can be stored in adipose cells actively and quickly, while the enlargement of muscle mass is a consequence of the increased weight. This is very bad.
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Losing weight is nothing mysterious. It lies in a basic physics law–energy intake should be less than energy expenditure. In plain English, if you eat fewer calories and spend more energy, you will lose your weight.

One popular idea is that you should lose your weight GRADUALLY –the slower, the better. For example, some advisors from MyFoodDiary.com suggest that if every day you reduce energy intake by 250 kcal and increase energy expenditure by 250 kcal, you will create an energy deficiency of 3,500 kcal in a week, and you will lose 1 lb fat. They also claim that when you lose weight slowly, you won’t lose too much muscle mass, and the body will not over-adjust the metabolic rate. It sounds biologically perfect.
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I like exotic foods. One of my favorite is salted red-yolk duck eggs. Except for the red yolks, making salted eggs is simple. After washing fresh duck eggs, you then put them in clean, salt-saturated water (one safe choice is the cooled boiled water). Wait for a few weeks so that salt can permeate the eggs thoroughly. Then you boil the eggs before serving them. They taste delicious.

But how come egg yolks have a red color? The answer lies in the duck’s diet. We know that a lot of foods have carotenoids such as beta carotene. If ducks eat foods that have a high concentration of carotenoids, they will lay eggs with yellow yolks. Similarly, if ducks eat foods that have red pigments, their egg yolks will become red.
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Addiction was traditionally restricted to substance abuse. Since the 1980s, researchers realized that the definition of addiction should be expanded to include behavioral addiction. For example, there are many people addicted to gambling, pornography, sex, and since the 1990s, computer use and the internet. Nevertheless, addiction is usually associated with negative things.

Is it possible that people are addicted to positive things? How about workaholic? Or even exercise?
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It has been two years since Iris Chang committed suicide in November 9, 2004. Many people tried to understand why she did that, but nobody can give a satisfactory answer. It seems to me that Iris is predisposed to depression and she might have set herself up when she started working on those arresting topics. Nevertheless, the death of Iris is a loss for all Chinese. Except for her untimely death, Iris lived a fruitful life and was a role model inspiring many Chinese Americans.

In memory of Iris Chang, I have thought a lot about depression recently. How can we treat depression? Medication is one choice, but only for those clinically diagnosed depressed people. For many mild cases and those who are always in blue mood, they need some other advice.
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Tonight when I was doing some research on procrastination, I came across Steven Pavalina’s blog (stevenpavalina.com). It is a fascinating site full of informative articles. In one of Steven’s best articles, he proposed one interesting regime to success: 30 days trial for anything. I sincerely agree with that.

I am a fan of self-experiment. During the past month, I put myself on a tough test: can I lose 20 lb of weight simply by exercise and calorie restriction? Happily, the answer is yes. I lost 20 lb within a month, an unprecedented achievement that deserves applause. This is an example of achieving success in 30 days.

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