I spied this report earlier this week. It concerns a study presented at a scientific meeting in Boston. Here’s what I can make out about the study according to the description.
69 overweight men and women were put on a controlled diet for 8 weeks. The diet was designed to maintain them at a stable weight. After this, the study subjects were fed a diet that offered 1,000 less calories each day for another 8 weeks.
Half the group ate a low fat diet (27 per cent calories from fat, and 55 per cent from carbohydrate).
The other half ate a diet higher in fat and lower in carb (39 per cent fat and 43 per cent carb).
At the end of the study, those eating the lower-carb, higher-fat diet had 11 per cent less ‘deep abdominal fat’ than the others. By ‘deep abdominal fat’ I assume their referring to ‘visceral’ fat – fat found in and around the abdominal organs that is strongly associated with an increased risk things like Type 2 diabetes and heart disease.
This different between the two diets was found in Whites but not Blacks. It was noted, in the report, that for a given body weight and composition, Whites tend to have more deep abdominal fat than Blacks. This means they stand to gain more, probably, from approaches that are effective for shifting this form of fat specifically.
Should we be surprised to learn that a bit of carb restriction can go a long way in combating visceral fat? Probably not – it’s becoming increasingly clear from the literature, I think, that eating too many carbs is what got the fat to form there in the first place.
Another interesting post on fats vs carbs John. I was interested to note that the blacks did not gain such a benefit as the whites. It is interesteing to speculate why.
Given the ethnicity of the USA, with the majority of blacks originating from West Africa, it seems plausable that their ancesters ate a higher carb diet than the whites. It would be interesting to know what factors (upregulated enzymes etc.) give them this advantage.
It is an important reminder that even if some diets are best for most people they will not be optimum for everyone.
So little reporting on how this applies to Native Americans who have a very high rate of diabetes and obesity.
I find it interesting that they got the results they got while only droping carbs from 55 to 43%. What would the results have been had they dropped the carbs down to the 10 to 20% range. It seems to me, based on my n=1 experience, that they real benefits of low carb start at 20%. I also think it is far easier to stay on a LC diet at lower percentages of carb intake.
I would agree with Robin that Blacks may have a greater tolerance for carbs than whites. But given what I see when I visit the city they do not have a pass to consume unlimted carbs. Perhaps their results would have been better on a lower percentage of carbs too.
43% carb is still fairly high. Would be interesting to see what would happen if they compare the low fat diet to a true low-carb diet.
The article states that the particpants ate 1000 fewer calories than their normal maintenance diet;
‘During the weight loss phase, subjects on both diets lost weight.’
No kidding! I count calories – every day. And watch proportions of macronutrients. I’d LOVE to be able to cut 1000 calories. Just point me to the clinic that makes that happen. I know that, for me, it’s friggin’ near impossible. It’s, um, a little over 1,000 calories a day.
And maintaining that – for life. NOT.