November/December 2010 Alternative Health
The Blood-Type Diet

by Dr. James L. D'Adamo

Early in my career, my studies in blood pathology led me to explore the possibility of a link between blood type and dietary needs.

The same way in which a medical doctor writes prescriptions for drugs to fight symptoms, I write menus, recommending (as needed) particular fruits, vegetables, animal proteins, and grains specific to an individual’s blood type, sub–blood type, and the current physical condition of his or her body. The same way in which most people take a drug to relieve a symptom, my patients use food to strengthen and balance their bodies, help protect them from losing their natural vitality, and in the case of a disease — heal the root cause of the problem.

Two of the most memorable case histories in my years of treating patients involve two young boys. In the first case, the boy, Roger, suffered with attention deficit disorder (ADD). It’s fairly normal for boys of nine to be highly energetic and active, and Roger was no different — he was in a state of perpetual motion.

However, there is a qualitative difference between being active and being frenetic. Like many children who have ADD, Roger couldn’t sit still or focus his mind for a prolonged period. At school, he was disruptive in the classroom, frequently shouting out during the teacher’s lesson or arguing with his classmates during recess, which often led to fights.

Roger had been treated by medical doctors and received the typical battery of medications, such as Ritalin, but with limited results. His parents brought him to me in my Toronto clinic as a last resort — many patients find their way into my office after they’ve gone the route of conventional medicine without finding much success.

Many conditions, including ADD, are a result of an imbalance in the body’s biochemistry and can be treated nutritionally and through vitamin supplementation. I explained that I work from the inside out and try to restore order to the body using nutrition, based on a person’s blood type. If they were willing to trust me and follow my recommendations — in Roger’s case to the maximum — we might be able to normalize his behavior.

ADD: An Inner Tsunami 

Roger’s blood was Type O. Generally speaking, the O has a robust and active nature and needs daily helpings of animal protein. I recommended that Roger follow a high-protein diet, starting with a protein shake upon rising before breakfast, and then eating an assortment of seven small servings of fish, meat, turkey, buffalo and/or lamb at two-hour intervals throughout the day.

I also greatly reduced his intake of carbohydrates — breads, pasta and mashed potatoes, all of which, when digested, break down into glucose. I immediately eliminated all sources of sugar from his diet including honey, candy bars, soft drinks, fruit juices, maple syrup (which Roger used in generous helpings on his pancakes on a daily basis) and any foods sweetened with high-fructose corn syrup (which also breaks down into pure glucose when digested).

It is now common knowledge — you can even see advertisements for high-energy drinks on television that refer to this — that sugar in any form, including fruit sugars, jolts the body with a wave of energy. To a boy with ADD or a disposition to hyperactivity, the ongoing jolts produce a chaotic, surging force. I liken it to a stormy internal sea. Imagine watching waves crashing into a shoreline or rocky coast. Sugar agitates and stirs the bloodstream with that same kind of wild energy.

Although it might not seem so, a body that is subjected to ongoing surges and is in constant motion is actually very tired and depleted. The constant intake of protein would supply slowly digested nourishment that, with the reduction of carbohydrates and sugar, would help even out Roger’s blood-sugar level, restore and rebuild his strength, and allow his body to find its inherent energy. A daily regimen of B vitamins, of doses specific to his condition and blood type, were also vital to nourishing and soothing his nervous system.

Roger responded to the diet fairly quickly and gained enough control over his emotional and psychological states so that within several months he was able to return to school where, for the first time, he started to excel.

Asthma and Diet  

The second boy, Ivan, suffered with severe asthma and frequently visited the ER, wheezing, coughing and gasping for air. He had Type A blood. People with Type A blood are highly sensitive to dairy products — a small glass of milk, a slice of cheese or a scoop of ice cream is like poison to their bodies. Ivan’s body reacted by producing an excessive amount of mucous plugs that clogged his airways.

I immediately eliminated all dairy foods, then wheat products, which are far too acidic for an A, and placed him on a strict vegetarian diet. The A is the only blood type that should be 100 percent vegetarian, although in some cases there may be traits of other blood types that can modify needs of an A.

Within weeks of following my recommendations, Ivan’s lungs cleared of the congestion, and he was able to stop using his steroid inhalator. He resumed a normal life, which included daily sports activities at school.

About two months later, however, Ivan was back in my office wheezing wildly. I suspected that he had gone off his diet and was again eating dairy products. Ivan’s mother confided in me that he often watched TV and ate ice cream and cookies at night when his father came home from work.

I rarely lose my temper with a patient, but I took Ivan’s father into the hall outside my office and read him the riot act. I told him that if he wanted to eat ice cream and cookies that was his business, but why destroy his son’s chance at a healthy life? Ivan’s mother made sure there were no more desserts in front of the TV set. Ivan’s asthmatic reactions again receded.

Today, modern medical doctors are gradually finding their way back to what Hippocrates proclaimed 2,500 years ago: “Let thy foods be thy medicine and thy medicine thy food.”

Dr. James L. D’Adamo is the author of Just an Ounce of Prevention is Worth a Pound of Cure: A Modern Guide to Healthful Living from the Originator of the Blood-Type Diet. Visit Excerpted with permission by Hay House at


November 2010 Cover