Once again I'm pondering the research around “diets.” First of all, I hate the word diet. It implies some sort of rigorous eating plan that once completed, will solve all your health problems and somehow miraculously allow you to resume former habits. Or, it alludes to something you hop on / off a couple times per year in hopes of staving off weight gain.
Diet is actually defined as the foods a person or animal habitats. In that sense, the way we use diet is all wrong. For most, “diets” have a foreseeable end, whereas a diet in actuality is the way you eat most of the time.
There are numerous “diets” or ways of eating that are being publicized. Who has not heard of the ketogenic diet by now? There is also paleo, Mediterranean, low carb, macrobiotic, vegetarian, vegan, etc. All of these tout that their plan is the “way” everyone should eat. It can be extremely confusing. It's like a pick your own adventure of diets.
Naturally, as a dietitian, everyone wants to know what I deem to be the BEST diet. Some are disappointed when I do not provide a clear and firm response on the matter. You see, the reason I keep pondering various these diets is because I've seen through countless client encounters that many diets, as healthy as they might seem, just plain do not work for some people . I have had people come in, desperate for help, because the “healthy” diet they have followed to the “t” is producing no weight loss results, or even worse, causing increased lipid levels and reduced energy. What gives?
Recent research out of Texas A & M may provide some helpful results.1 They showed that in mice fed various popular diets (Standard American, Ketogenic, Japanese, Atkins, etc), they all responded differently, some positive and some negative. In other words, some mice showed positive improvements on particular plans while others actually got worse on the very same diet.
The key is genetics. The researchers in this study suspect that genetic variations cause our bodies to respond better or worse to various foods and styles of eating. For example, one mouse in particular did very poorly on the Japanese diet, surprisingly, while the rest stayed in good health. Also, most did poorly on the standard American diet (as expected) but some fared less poorer than others.
The take home message is that clearly, one diet does not fit all. A diet that improves the health of one person may worsen the health of another. So many out there want to promote and sell you the universal “ideal” diet, and yet it is becoming more clear that it does not exist. The role of genetics is only going to continue to become more prominent as we search for answers in the obesity epidemic and for conditions such as heart disease, diabetes and hypertension.