In the first post in the series A Skeptical Look at Popular Diets, physician Randall Stafford writes that picking a particular diet is not that important.

Despite the raging food wars trying to define the best diet, finding the right popular diet may not be that important. Rather, it’s all about properly implementing the diet you select. While some diets are inherently healthier than are others, the truth is that you can sabotage any diet through bad food choices. Conversely, you can redeem some questionable diets through good choices.

Just to be clear, I’m talking about a “diet” as a consistent pattern of adults selecting foods following basic guidelines (not just eating to lose weight). After both patients and colleagues bedeviled me to identify the best possible diet, I concluded that no simple answer existed.

Many of the leading popular diets emphasize simple rules that make food choices easier to follow. One diet may call for avoiding meat, another for eliminating sugar, still another may shun all wheat products. It can be helpful to place restrictions on how we eat to make us more consistent about our dietary habits. Firm rules provide needed structure. We usually do better if we can avoid difficult, last minute, and often impulsive decisions about what we put in our mouths. Given the abundant evidence that what we eat affects our long-term health, following a set of rules can be good idea.

When diets call for avoiding specific foods, this creates the opportunity or need to decide what foods to substitute in their place. For most diets, this flexibility opens the door to both good and bad choices. It's not helpful to avoid saturated fats and at the same time overindulge in low-fat cookies. Conversely, replacing a daily donut with a green smoothie could be a good move.

Proponents spend much effort convincing people that this or that popular diet is the best. But the choices made within any particular diet are more important.

In the coming weeks, I will be reviewing eight of the most popular diets out there. Christopher Gardner, PhD, my Stanford colleague and nutrition specialist, will help me explain these popular diets. We will be looking at their scientific basis as well as how to make them better or worse.

These diets cover a huge territory, ranging from the caveman-inspired paleo diet to vegetarian diets, from low-carbohydrate diets to a Mediterranean diet. As different as these diets might seem at first glance, a healthy version of any one of them get pretty close to what we need for great health. Gardner figures, in fact, that the true benefits of all of these diets are captured in five basic rules for healthy eating:

Eat more fibrous vegetables Eat more whole foods (the opposite of highly processed snack foods) Greatly reduce sugars and foods with added sugar (often in junk foods) Minimize the intake of foods made with white flour or other processed starches Eliminate trans-fats and moderate the intake of animal-based saturated fats

Here are the slogans of the popular diets we’ll be reviewing in the next several weeks:

Paleolithic — Don’t eat any food that wasn’t around 10,000 years ago

Low-fat — Avoid fats in your diet, regardless of their source

Vegetarian — Get the health benefits of not eating meat with ethical and environmental bonus points

Low-carb or Atkins — Eat all the bacon you want, as long as you cut out sugars and starches

Ketogenic — Eat so few carbs that your body has to use fat as its main source of energy.

Gluten-free — Avoid any foods that contain wheat or barley

Mediterranean — Follow the culinary path of the great Mediterranean civilizations with many "good" fats

Raw food — Eat only uncooked foods; if it cannot be eaten raw, don’t eat it.

This is the first post in a series called A Skeptical Look at Popular Diets. The series will review the eight currently most prominent diets in America. The next blog post will discuss the so-called caveman or paleolithic diet.

Randall Stafford, MD, PhD, is a professor of medicine at Stanford. He practices primary care internal medicine and studies strategies for preventing chronic disease. Stanford professor and nutrition scientist Christopher Gardner, PhD, examines the impact of diet on health and disease. Min Joo Kim and Sophia Xiao provided research assistance.

Photo by moreharmony