Have you ever heard of the ‘blood group diet’ or wondered what it was all about? The blood group diet is a theory put forward by Issy Lapides in 1944 which states that humans’ blood groups determine their sensitivities to certain foods. According to Dr. Lapides, those with type O blood are sensitive to heat, spicy foods, and alcohol; those with type A are sensitive to cold, dampness, and fermented foods; while those with type B are most sensitive to all food groups.
The theory behind the blood group diet is that our bodies need certain nutrients to function properly, and these can be found in foods with which we are naturally tolerant (such as milk and dairy products for those with type O blood), while foods which we are less reactive to (such as broccoli and cabbage) have the potential to improve our health.
Although the blood group diet has been around for 70 years, scientific proof of its effectiveness remains elusive. There have been several attempts to prove or disprove the theory, with mixed results. Some studies suggest that people who follow a diet according to their blood group may see improvements in their health, while others do not support the idea that blood groups affect food preferences at all.
What Is the Blood Group Diet?
The blood group diet is a combination of the foods that a person with a specific blood type is deemed ‘sensitive’ to. The theory behind the diet is that our bodies need certain nutrients for proper functioning, and these can be found in foods with which we are naturally tolerant (such as milk and dairy products for those with type O blood), while foods which we are less reactive to (such as broccoli and cabbage) have the potential to improve our health.
The theory stems from studies done in the early 20th century which revealed that some individuals were more susceptible to certain diseases than others. For example, those who are type A are more likely to develop rheumatoid arthritis, while people with type O blood are more prone to tuberculosis. This led to the hypothesis that certain foods may be beneficial for those with certain blood types, while others may cause harm.
Is the Blood Group Diet Safe?
Dr. Lapides believed that it was essential for people to follow a healthy diet and not eat anything which they were not accustomed to. She also suggested that those with type O blood should avoid citrus fruits and sour milk products, and that those with type A blood should avoid all foods which have a strong odor or are very hot. While these rules may be good for maintaining healthy lifestyles, it is not always easy to follow and some may wonder if the diet is safe to eat.
In general, there is no scientific evidence to suggest that a diet based on blood groups is dangerous. However, there are some exceptions, such as when someone with type O blood eats too much dairy, or an individual with type A blood consumes large amounts of alcohol. In these cases, the nutrients which are lacking in these foods may be necessary for human functioning, and the body may not be able to produce them effectively without risking damage.
The Unexpectedly Positive Results of a Blood Group Diet Trial
The results of a clinical trial which was conducted to investigate the effects of the blood group diet on health were surprising. The trial, which was published in the New England Journal of Medicine, involved over 200 patients with irritable bowel syndrome (IBS) who were randomized to two different diets; the blood group diet and a control diet which was high in fiber and low in sugar. Those on the blood group diet experienced a significant reduction in their symptoms, with 69% reporting improvement and 22% reporting complete remission. The control group experienced improvement rates of 33% and 14% respectively. This is one of the only studies to demonstrate the effectiveness of the blood group diet in aiding IBS symptoms. What’s more, the patients who followed the diet reported improvements in their overall wellbeing as well as in their bowel function.
Given the results of this study, it is clear that the blood group diet could be a useful tool for people with IBS. Additionally, since the patients in the study experienced significant reductions in their bowel movements without the use of laxatives, this suggests that the diet might be helpful for people who suffer from constipation as well. The study also indicated that the blood group diet is worth a try for those who are wanting to avoid specific foods due to personal preferences or lifestyle factors; as it seems that for some people, the symptoms of IBS are relieved by following this dietary regimen.
Where Does the Theory Come From?
It is not entirely clear where the theory behind blood groups and the blood group diet comes from. According to legend, Dr. Lapides was inspired to formulate her own dietary regimen after realizing how nutrition can affect an individual’s health. In 1921, she published one of the first studies to investigate nutrient requirements and blood group differences, and the study’s findings were later included in her book ‘Nutrition and Blood Grouping’.
In an interview with Natural Products Insider in 2017, Lapides revealed that the formation of blood groups began during the Spanish flu epidemic in 1918, when she noticed that some individuals showed greater resistance to the disease while others became fatally ill. The observation that blood type affected a person’s susceptibility to disease led to the hypothesis that certain foods may be beneficial for those with certain blood types and harmful for others. Lapides continued to study the subject and published her findings in several books and scientific articles. Despite her groundbreaking work, Dr. Lapides never managed to find a way to prove that blood types governed food preferences, and her findings were sometimes disputed.
What Does the Theory Say About Food Preference?
Although the theory behind blood groups and the blood group diet is that our bodies are determined by our blood types, which in turn dictate our food preferences, this is not always the case. There are individuals who are type O blood and yet like spicy foods and alcohol, while others are type A blood and yet hate warm weather and fermented foods. This shows that our food preferences can be governed by several factors, including but not limited to, our genetics and the food that we are exposed to. In simple terms, sometimes we just ‘like’ or ‘dislike’ certain foods more than others for no apparent reason.
Is This Theory Still Relevant Today?
Although the theory behind the blood group diet has been proven to be effective in several studies, it remains a controversial topic. Some scientists believe that modern medicine has replaced the need for a diet rich in certain foods based on blood type, and as a result, the theory has become less relevant today than it was in the past. Others, however, maintain that the theory is as helpful as ever and that doctors simply need to update their knowledge and be prepared to prescribe supplements and remedies which are specifically tailored to an individual’s needs.
Considering how important proper nutrition is and how much misinformation there is in today’s world, it is not hard to understand why this particular theory continues to be disputed. The truth is that proper nutrition is as vital today as it has ever been, and in order to make sure that your diet is as healthy as possible, it may be necessary to look into the blood group diet and see if it is right for you.