There’s something deeper going on with food and fat. It’s something beyond calories in and calories out, something that science doesn’t yet fully grasp.
Apart from simply being more filling, there seems to be a deeper reason that whole foods can lead to a lifetime of leanness: the body-fat set point.
Although we don’t know exactly how it works, it’s obvious that the human body “defends” fat stores at certain levels, or “set points.”
Set points are why weight tends to creep back on after weight loss.989 On the other hand, set points are why, when someone goes on an uncharacteristic eating binge, they tend to lose the weight they gained.990,991
Most convincingly, set points are why many people manage to maintain nearly the exact same weight for years on end without any conscious thought or effort, somehow managing to eat exactly the same number of calories that they expend over very long stretches of time.992
Think about that.
Like a thermostat, despite fluctuating environments, the human body is capable of maintaining fat stores at very precise levels for very long periods.
Until quite recently, the vast majority of humans defended fat stores at relatively low levels. This is still the case for modern hunter-gatherers and people living in several traditional societies.993,994,995
Something in the modern environment has dramatically raised our body-fat set points.
Something has changed profoundly.
The most obvious culprit is diet.
Our body-fat set points are affected by the kind of foods we regularly eat. This has been demonstrated in animal models. When susceptible rats are fed highly palatable diets and allowed to eat freely, their body-fat set points increase dramatically: the rats gain lots of weight, and maintain this weight gain. (They don’t just keep gaining weight forever.)
But when rats are switched back to less palatable diets and allowed to eat freely, their body-fat set points plummet: many rats lose lots of weight, and maintain this weight loss.996,997
(They don’t just keep losing weight forever.)
Something similar happens to humans.
When processed food is freely available, humans spontaneously overeat and gain fat.998,999,1000 In other words, a diet of processed food causes the human body to store more fat.
But when humans start eating a bland diet and eat freely, trials show that they tend to lose weight quickly1001—especially when they’re obese.1002
An interesting study from 1965 vividly illustrates how changing the kinds of foods you eat could dramatically lower your body-fat set point.
In a hospital setting, normal-weight and obese subjects were put on a bland liquid diet. The bland liquid contained 50% carbs, 20% protein, 30% fat, and some vitamins and minerals. (It probably tasted like a watered-down Ensure.)
The subjects were allowed to drink as much of this liquid as they wanted, but could eat nothing else.
So what happened?
The leaner subjects drank enough of the bland liquid to maintain their weight over the study. The obese subjects, on the other hand, drank very small amounts of the bland liquid.
They quickly started losing lots of weight.
In 12 days, one obese woman lost 23 pounds.
In 18 days, an obese man lost over 30 pounds. Despite consuming far fewer calories than his body needed to maintain his weight, the man never reported feeling hungry. Seeing the potential of this approach, he continued the diet at home, in a modified form, for 252 days after the study.
He lost 200 pounds.1003
His lack of hunger suggests that the bland liquid diet had somehow caused his body to start defending fat stores at a lower level. With nothing to eat except bland protein shakes, maybe his body decided it wasn’t worth it storing all that fat.
Switching from a diet of processed foods to a diet of whole foods may accomplish something similar. While many whole foods are delicious, they do tend to be blander than hyper-palatable processed foods.
Indeed, the most common weight-loss strategy used by members of the National Weight Control Registry—a group of people who have lost a lot of weight and kept it off—is to modify their diet.1004
And the most common way that they modify their diet is by restricting certain foods.1005 And dietary consistency is one of the best predictors of long-term success in the National Weight Control Registry.1006
In other words, people who successfully lose lots of weight and keep it off manage to lower their long-term body-fat set points by changing the foods they regularly eat—specifically, by restricting certain foods.
Sound familiar?
References
989. Ayyad C., and Andersen, T., “Long-Term Efficacy of Dietary Treatment of Obesity: A Systematic Review of Studies Published Between 1931 and 1999,” Obesity Reviews 1, no. 2 (2000): 113-119.
990. Diaz et al., “Metabolic Response to Experimental Overfeeding in Lean and Overweight Healthy Volunteers,” American Journal of Clinical Nutrition 56, no. 4 (1992): 641-655.
991. Pasquet, P., and Apfelbaum, M., “Recovery of Initial Body Weight and Composition after Long-Term Massive Overfeeding in Men,” American Journal of Clinical Nutrition 60, no. 6 (1994): 861-863.
992. Frayn, Keith. Metabolic Regulation: A Human Perspective. Oxford: Wiley Blackwell, 2010. Kindle File, 12.4.2, Location 7824-40.
993. Marlowe, F., and Berbesque, J., “Tubers as Fallback Foods and Their Impact on Hadza Hunter-Gatherers,” American Journal of Physical Anthropology 4 (2009): 751-8.
994. Lindeberg, Staffan. Food and Western Disease: Health and Nutrition from an Evolutionary Perspective. Hoboken: Wiley-Blackwell, 2010. Kindle File, Chapter 4.5, Location 3065.
995. Ngoye et al., “Differences in Hypertension Risk Factors between Rural Maasai in Ngorongoro and Urban Maasai in Arusha Municipal: A Descriptive Study,” Journal of Applied Life Sciences International 1, no. 1 (2014): 17-31.
996. Levin, B., and Dunn-Meynell, A., “Defense of Body Weight Depends on Dietary Composition and Palatability in Rats with Diet-Induced Obesity,” American Journal of Physiology: Regulatory, Integrative and Comparative Physiology 282, no. 1 (2002): R46-R54.
997. Levin, B., and Keesey, R., “Defense of Differing Body Weight Set Points in Diet-Induced Obese and Resistant Rats,” American Journal of Physiology 274 (1998): R412-R419.
998. Larson et al., “Spontaneous Overfeeding with a ‘Cafeteria Diet’ in Men: Effects on 24-Hour Energy Expenditure and Substrate Oxidation,” International Journal of Obesity and Related Metabolic Disorders 19, no. 5 (1995): 331-7.
999. Larson et al., “Ad Libitum Food Intake on a ‘Cafeteria Diet’ in Native American Women: Relations with Body Composition and 24-H Energy Expenditure,” American Journal of Clinical Nutrition 62, no. 5 (1995): 911-917.
1000. Risling et al., “Food Intake Measured by an Automated Food-Selection System: Relationship to Energy Expenditure,” American Journal of Clinical Nutrition 55, no. 2 (1992): 343-9.
1001. Cabanac, M., and Rabe, E., “Influence of a Monotonous Food on Body Weight Regulation in Humans,” Physiology & Behavior 17, no. 4 (1976): 675-678.
1002. Hashim, S., and Van Itallie, T., “Studies in Normal and Obese Subjects with a Monitored Food Dispensing Device,” Annals of the New York Academy of Sciences 131, no. 1 (1965): 654-661.
1003. Ibid.
1004. “NWCR Facts,” National Weight Control Registry. https://www.nwcr.ws/Research/default.htm
1005. Wing, R., and Phelan, S., “Long-Term Weight Loss Maintenance,” American Journal of Clinical Nutrition 82, no. 1 (2005): 222S-225S.
1006. Ibid.