Q1: Among the three macro-nutrients (protein, fat, carb) is there a dominant contributor to my BMI and my daily calorie intake?

For many years (since my teenage years) I basically believed the Singapore public health message that by far the biggest macro nutrient responsible for My weight gain is various forms of fat such as

• butter, ghee
• fried foods
• creamy soup, creamy cake, ice creams
• visible fat in meat; skins; organs
• floating fat

At the same time, I believed that unflavored, steamed/boiled/baked starch was completely innocent, including rice, bread, noodle,,,

Sometime in 2013, My friend Patrick Foo changed my view. I started /controlling/ my rice intake, and saw quick results in BMI improvement. I attributed it to the indirect reduction in fat intake.

Around 2017 in New York I noticed for the first time that many online articles targeted carbs as a key contributor to weight gain. These authors regard carbs as equally responsible as fat. I was skeptical.

In 2018 I started cutting back my daily starch intake from around 1200~1500 calories to as low as 100 calories. I came to the startling realization that the lion’s share of my daily calorie intake traditionally come from starch excluding sugar.

Now in 2020, My answer to Q1 is starch, while a distant second biggest contributor is fat, because I have avoided fat all my (adult) life. Between fat and starch, I have no doubt that animal fat is more calorie dense, and starch is less harmful to my health but my diet habit since childhood includes 10 times more starch than fat. I believe my “system” is different from most people. I eat more starch than everyone I know. If we ask every individual in my age group

Q2: What percentage of your daily calorie intake comes from starch?

, then my answer probably puts me in the highest percentile i.e. higher than 99% of the population..

1. In my teenage years, I used to eat very little protein, vegetable, fruits, fat and sugar.
2. In my 30’s and early 40’s when I reduced my fat and sugar intake and increased veg and fruit intake, my answer to Q2 remained extremely high.
3. When I cut back my starch intake, I had to eat an uncomfortable amount of other foods to compensate. A major lifestyle adjustment.

Now I would venture to say my BMI is largely determined by my daily starch intake. Starch intake would probably come out in a Principal component analysis (PCA). Whenever I managed to reduce my starch intake my BMI would improve.