Blood type O is the most common blood type, making up about 45% of the population. There has been some speculation around whether people with type O blood should avoid dairy products due to potential digestive issues. Here is a look at the evidence around blood type O and dairy.
The Blood Type Diet
The blood type diet, created by Dr. Peter D’Adamo, suggests that people with different blood types should follow different diets. The theory is that blood type affects the immune system and digestion in a way that makes certain foods more or less beneficial for you.
According to the blood type diet, those with type O blood should generally avoid dairy products. This is because Dr. D’Adamo claims that people with type O blood have insufficient levels of an enzyme called intestinal alkaline phosphatase which is needed to properly metabolize dairy.
What the Research Says
While the blood type diet has been popular, there is limited scientific evidence to support its claims. Here is what the research says so far on blood type O and dairy:
- There have not been any rigorous studies confirming that type O individuals have lower levels of intestinal alkaline phosphatase than those with other blood types.
- A review published in the American Journal of Clinical Nutrition looked at the evidence for the blood type diet’s recommendations and found no studies that offered significant support. The researchers concluded that “no evidence currently exists to validate the purported health benefits of the ABO blood type diet.”
- A study in PLOS One looked at over 1,000 participants and found no significant difference in dairy digestion between those with blood types O, A, B, and AB.
Based on the current research, there is no strong evidence that people with type O blood need to avoid dairy due to digestion issues. More research is still needed looking specifically at blood types and digestion.
Potential Benefits of Limiting Dairy
While people with type O blood do not necessarily need to avoid dairy, there may be some potential benefits for some individuals if they limit dairy intake:
- Lactose intolerance – About 65% of adults have some degree of lactose intolerance, which can cause digestive issues from dairy. Type O individuals may have a slightly higher risk of lactose intolerance.
- Inflammation – Dairy may increase inflammation in some people. Since type O is prone to inflammation, limiting dairy may help.
- Weight loss – Replacing dairy with lower calorie options can aid weight loss for those needing to lose weight.
Risks of Dairy Avoidance
While limiting dairy may provide benefits for some, there are also some potential risks to keep in mind:
- Dairy products provide calcium, vitamin D, potassium and other important nutrients. Avoiding dairy may make it more challenging to obtain adequate amounts of these nutrients.
- Going dairy-free can remove a major source of protein from the diet. Non-dairy sources of protein like legumes, nuts, eggs and meat should be included.
- Those with a history of disordered eating may be triggered by overly restrictive diets that cut out entire food groups like dairy.
Tips for Incorporating Dairy
Instead of strictly avoiding all dairy products, here are some tips for people with type O blood to incorporate dairy in a healthy way:
- Stick to moderate portions of dairy rather than overdoing it.
- Choose low-fat or non-fat dairy options to limit saturated fat intake.
- Try probiotic yogurt and kefir, which may be easier to digest.
- Limit lactose by choosing lactose-free dairy, aged cheeses, and yogurt.
- If needed, take a lactase enzyme supplement when consuming dairy.
- Opt for non-dairy milks like almond, soy or oat milk fortified with calcium and vitamin D.
- If you have noticeable digestive issues from dairy, try eliminating it for 2-3 weeks then reintroducing while paying attention to symptoms.
Summary
While the blood type diet recommends that those with type O blood avoid dairy, there is limited evidence to support this. With a balanced and moderate approach, most people with type O blood can likely include some dairy products without issue. Focus on getting enough nutrients from a variety of sources and pay attention to any digestive discomfort. Those with lactose intolerance may need to limit dairy more strictly. However, there is no need to unnecessarily restrict dairy without a diagnosed reason.