A Daily Webzine Celebrating The Wonder Of Individuality & The Blood Type Diet®

Blood and Bone


By Peter D’Adamo

The process of bone breakdown and repair occurs throughout life. With osteoporosis, the calcium that keeps bones strong is lost and new bone formation stops occurring to repair bone loss. The result is that the skeleton becomes fragile, and the bones grow thin and brittle.

Bone loss happens over time, accelerating with age and menopause. To some extent, every person, male and female, experiences a degree of bone loss with age. But it’s a far less severe problem for men, since they start out with about 30% more bone mass than women and tend to lose it more slowly. It’s also less severe in women who have darker skin; because they have about 10% more bone mass than women of European or Asian ancestry or who have fair skin.

To a surprising degree, your bone health is linked to physiology that is controlled by your blood type.

Hip fractures among elderly women are a costly and devastating epidemic in this country. Osteoporosis carries a $7 billion annual medical price tag, and $5 billion of that is due to hip fractures. Aside from the cost, hip fractures are associated with high morbidity and mortality. Falling down is the leading cause of death among people over age 75, mainly among women. All patients with hip fractures require hospitalization and between 12% and 20% die during the first year. Of those who survive, 50% will never walk independently again.

Risk factors for osteoporosis include:

  • Family history – especially a mother with osteoporosis
  • A thin and small fame
  • Light skin
  • A sedentary lifestyle
  • Excessive consumption of alcohol and caffeine
  • Low muscle mass
  • Taking calcium-depleting medications, such as cortisone
  • Pre-menopause hysterectomy or early menopause
  • Smoking
  • Eating disorders


The Calcium Connection

Calcium is a mineral essential for building bones and teeth and for maintaining bone strength. Bones and teeth contain 90% of the body’s calcium stores. When bones don’t contain enough calcium, they weaken. The body’s ability to absorb calcium is influenced by the form in which it is taken, its interaction with other nutrients, and the way it is absorbed into and eliminated out of the body.

Certain nutrients have a direct affect on calcium absorption. Vitamin D, which is converted into a hormone called calcitriol, regulates the transport of calcium from the digestive tract to the bloodstream and into the bones. Phosphorous is another mineral that has an effect on bone density. Too much or too little phosphorous in the body can harm bone formation. Magnesium is important for the body’s utilization of calcium and vitamin D.

Protein is vital to the formation of bones, but too much protein can increase the amount of calcium lost in the urine. When protein breaks down in the body, it produces organic acids, and the body pulls calcium carbonate out of the bones to act as a buffer. So, although too little protein can damage bones, too much can weaken them. However as I will detail in a future article, this is far from a universal truth, especially when blood type and secretor status are factored into the calculations.

Medications can also leach calcium from the system, for example thyroid hormone encourages bone loss. Other medical treatments that can deplete calcium include cortisone, chemotherapy, long-term lithium therapy, anti-convulsants, and long term use of phosphate-binding antacids. Endocrine disorders can also contribute to osteoporosis. These include hyperthyroidism, hyperparathyroidism, Cushing’s syndrome, and Type 1 diabetes.

Blood Group Links

Blood group A has the highest incidence of osteoporosis for two reasons. First, evidence suggests that intestinal alkaline phosphatase enzyme, in addition to enhancing fat breakdown, also enhances the absorption of calcium. Groups A and AB are known to have lower levels of intestinal alkaline phosphatase. On the other hand, groups O and B, with higher levels, are less susceptible to osteoporosis, especially if they keep their dietary intake of protein in the high side. In addition, people with higher stomach acid tend to absorb calcium more efficiently, giving groups A and AB, with naturally low stomach acid levels, a disadvantage.

Calcium exists in a sort of dynamic equilibrium with another mineral, magnesium. My experience has shown that the optimum ratio of calcium to magnesium tends to vary by blood type and secretor status.

Dr. D’Adamo has designed highly absorbable calcium supplements that are individualized for each Blood Type –

Image: Ilya Mashkov, ‘Still Life with Skull’ (c.1910)


Dr. Peter D'Adamo is a naturopathic phyiscian, author, researcher-educator and software developer. He is considered a world expert on glycobiology, principally the ABO blood groups and the secretor (FUT2) polymorphisms. He is the author of the international best-seller, Eat Right 4 Your Type and the Blood Type Diet series of books, and he is currently a Distinguished Professor of Clinical Sciences at the University of Bridgeport, Connecticut.

Categories: Blood Type Physiology, Learning, Peter D'Adamo, Science