Why is it that two people can do the exact same diet yet get dramatically different results?
That was the question asked by researchers at Stanford University as they partnernered with Interleukin Genetics, a company that develops genetic tests, to determine if genetic predispostions affect which diet plan will work for a person.
The results? Yes, genetics does play a role. Subjects whose diet matched their genetic predispostion lost 5.3% of their pre-diet body weight. The subjects whose diet did not match their genetics only lost 2.3%.
The current study, presented to an American Heart Association conference, built on the findings of Stanford’s A to Z diet study.
The A–Z study compared the Atkins, LEARN, Ornish and Zone diets.
Atkins came out ahead in the A–Z study, but there were wild variations in the groups following each diet. Some subjects could lose 30 pounds on the Atkins diet while others barely lost 10.
Other subjects lost weight on the low-fat Ornish Diet, while others gained weight on Ornish.
The role of genetics should not be surprising. Everyone’s metabolism is a little different and some people’s, like mine, are downright cruel.
I have a double whammy metabolic problem. I’m insulin resistant, which means my body does not process carbs and sugars well, and my muscles do not absorb and hold glycogen.
What that means is a high carbohydrate diet, even if it produces a caloric deficit, will not result in much if any fat loss for me. The carbs I eat are turned into blood sugar and then directly deposited into fat.
And as it turns out, 45% of white women are genetically predisposed to be more successful on a low-carb diet.
For people who are low-carb genotype, a ketogenic diet like the ones Nita Marquez and I describe in our book Fit for Combat can lead to dynamic fat loss.
For fat loss and reshaping your body, a low-carb, high protein diet when combined with weight training is still the best path because of the metabolic synergy–it tricks the body into burning fat as the primary source of energy while allowing it to increase muscle tone and size that leads to a higher resting metabolic rate.
For the low-fat genotype, a high protein, low-carb diet when combined with weight training delivers the same synergy when fat intake is controlled.
The genetic testing is still a long way off from being perfectly dialed in to guide a person, but determining the right diet to fit into your favorite pair of jeans has a lot do with your genes.