One of the most popular diets in recent years has been the Blood Type Diet, which suggests that people eat foods most agreeable with their genetic blood type. There are books, videos, social support groups, and plenty of related literature on the topic, as well as a massive body of medical opinion that counters much of the advocates’ claims.
What exactly is the BT diet, where did it come from, who are its main proponents and what does the scientific research community think about the program? To put the diet in perspective, it helps to examine fad diets in general and see why they are routinely ineffective.
Since the 1980s, there have been more than 100 different diets touted by their creators. While most are weight-loss oriented, some claim to “cure” or treat various physical ailments, and others are said to enhance consciousness or add years to one’s life. Like any other category of consumer products, diet plans and books (there is invariably a best-seller behind each of the new regimens) have an upside and a downside.
The Blood Type Diet, popularized in a best-selling book, offers different eating plans based solely upon a person’s blood type, whether it’s AB, O, A or B. The original BT diet was created by a naturopathic physician and has come under assault from a variety of sources.
Facts and figures about the BT diet:
The diet is based on the assumption that every food a person consumes has a specific chemical reaction with their blood, based upon the type of the blood. If the chemical reaction is favorable, then the food will digest more efficiently. Added benefits are said to be weight loss, disease prevention and elevated energy levels.
The breakdown for who can eat what goes something like this: Persons with type O blood should stick to a meaty diet high in protein, dairy, beans, grains and vegetables. Anyone with type A blood is told to avoid meat and emphasize vegetables, fruits, whole grains and legumes. There is an additional recommendation that as much of this food as possible be fresh and organic. Those with type B blood are told to eat low-fat dairy, eggs, some meats, and green veggies. Finally, type AB blood calls for dairy, tofu, green veggies, and tofu. They are instructed to avoid cured/smoked meats, alcohol and caffeine.
Once a person finds out what their blood type is (many do not know), the diet is relatively simple to follow. There are no pre-packaged foods to buy from a special club and no meetings to attend. But, following the regimen can be difficult due to the restrictions for each blood type.
Many people who go on the diet report significant weight loss, as least in the beginning stages. This is likely a result of the strict recommendations and lists of forbidden foods.
The BT dies also comes with a set of exercise suggestions, which are, you guessed it, based on one’s blood type. Type O dieters, for example, are told to engage in activities like running or bicycle riding for about one hour each day, while type A’s get off a bit easier with the recommendation to do tai chi or yoga.
As diets go, the BT regimen is pretty strict, with few exceptions allowed on the food lists. And along with the type-specific exercises, there are also condiment and spice suggestions based on blood type as well.
Fans of gluten-free eating will face confusion on the BT diet because it does not list foods by their gluten content. To make the situation even more perplexing, the BT diet recommends various herbal supplements, vitamins, organic foods and specialty products.
Major medical studies have concluded that while the BT diet does not appear to be dangerous, it does not deliver on the promised benefits of eating specific foods based on blood type.
One of the big objections the medical community has to the BT diet related to specific health conditions. For example, diabetics under a doctor’s care are usually told to eat from every major food group and maintain a traditionally balanced diet. The BT diet can conflict with that advice depending on what someone’s blood type is. The same problem arises for those who have problems with cholesterol, blood pressure regulation, heart disease and other serious conditions.
Some medical professionals take exception to the BT diet’s exercise recommendations, noting that most everyone should exercise regularly and include aerobic workouts in a well-balanced routine. The BT diet has people with different blood types doing different kinds of exercise, which seems to go against logic.
Weight loss in the BT diet usually results from the restrictive overall nature of the regimen and its avoidance of simple carbohydrates and processed food products. There is no research evidence that weight loss on the BT diet has anything to do with a person’s blood type.
The creator of the BT diet sells a line of food supplements that he recommends; he also strongly emphasizes eating organic foods. This means that people on the BT diet will end up doing a lot of their own food prep (not a bad thing, but it takes some by surprise), and probably spending more money than they would on a more ordinary eating plan.
People who want to lose weight are typically told by medical professionals to eat a well-balanced diet based on all the food groups, avoiding processed and junk food when possible. Exercise, too, is never tied to one’s blood type but is more often calibrated to one’s age and physical ability. In short, there is very little mainstream scientific support for the BT diet.
The dangers of so-called “fad diets”
Some people categorize the Blood Type Diet as a modern fad diet. Whether this is accurate or not, there are some common elements of fad diets that consumers should be aware of.
Most medical professionals recommend against quick weight loss, noting that it can be a dangerous practice. Fad diets promise rapid weight loss and should be avoided for that reason alone.
Fad diets usually have at least one or two severe food restrictions which can lead to an unbalanced state of health.
Quick weight loss can lead to dehydration and other severe problems with regularity and constipation.
Severe caloric restriction can cause serious energy deficiencies. It is rather common for beginning dieters to fall asleep at work or after lunch during the first few days of a fad diet. The body simply runs out of calories and begins to shut down by going to sleep.
Weight loss on fad diets almost always comes from water loss, especially in the early stages. This is quite a dangerous thing for the body because it requires a sufficient amount of water to supply the blood and perform other vital functions.
Fad diet weight loss is nearly always temporary. In fact, there have been studies that demonstrate a rebound effect of such extreme dieting. Those who lose lots of pounds early on are subject to even greater weight gain in the long run.
Anyone who wants to lose weight or go on a diet or exercise plan that is new for them should consult a physician before doing so. Eating a balanced meal plan each day and taking part in regular exercise is usually all it takes to maintain a healthy weight.