Comment

Comment by niels_olson

Here's the original article. http://www.nejm.org/doi/full/10.1056/NEJMoa1007137.

The study is impressively well done, as are most articles in the New England Journal. Other researchers will be studying their methods as much as their results.

> Without a comprehensive listing of specific meals

Actually, they did better and developed local indexes for all foods for each center and had the patients keep food diaries.

> Further, gaining a pound of fat over a period of 6 months works out to less than 20 extra calories per day. This is essentially noise.

First, this is why we enroll more than one patient. The noise averages out. Two: the unit of measure was kilograms, the average arm gained more than 1 kg. Three, see figure 2B in the article: they quite nicely demonstrate sufficient granularity to appreciate signal.

> Keeping your blood sugar in check is a major factor in preventing binge eating and fat storage

> people engaged in sustained cardiovascular exercise must eat high-GI foods or their performance drops

Your liver has glycogen stores on board that will keep your blood sugar rock steady for the first 20 miles of a marathon. Unless you are exercising at a heart rate of 160-180 for 2.5 or more hours, this is useless trivia.

> Riders in the Tour de France chow down on every sugary snack and drink known

> Michael Phelps eats 12,000 calories a day while training.

Some of the most over-cited factoids on the Internet. I swam competitively for 7 years and raced bikes competitively for four, and still ride. I'm also a doctor who spent a fair amount of a surgical internship with the bariatrics unit. These facts about elite athletes do not bear on anyone who has a BMI of 34 (Patients are generally ineligible for bariatric surgery below a BMI of 35)), the average human, or, almost certainly, you. A far more useful factoid is that your glycogen stores are depleted overnight, so a 2-3 hour cardio session in the morning will force you to burn fat. The body has no other choice. (No, it won't burn muscle).

> if you are completely sedentary, if you are engaged in a mentally taxing task, your brain is burning through a lot of glucose

Normal adult human brain uses, 120 g to, maybe, 220 g of glucose per day. At the outside, that's 750 Calories.

> sucrose means half glucose and half fructose, and only the glucose can be metabolized immediately. Fructose can be stored by the liver and converted, but if the liver reserves are full (e.g. late in the day, as opposed to waking up from fasting during sleep), fructose will end up as fat. Fructose has a low glycemic index,

True. Unfortunately, your implicit conclusion . . .

> guess which sugar is more likely to be included in a low-GI diet

Is what? Are you saying they loaded these cats with fructose? If they did, then these results are even more impressive, because we would expect a high fructose diet to promote fat gain. Are you saying they loaded them with glucose? That would make no sense, because glycemic index measures "blood glucose".

> Finally, without body composition analysis, they haven't shown anything about fat loss.

See Table 2 of the study.

parent niels_olson 16 years ago

Discussion

Live from the official Hacker News API

A modern reader for Hacker News · SvelteKit + Skeleton