system of the body can be affected, be it the nervous, digestive, cardiovascular or hormonal system. Lectins are proteins that can bind to any molecule with a sugar portion on the surface of its cells. And precisely the way our blood type is expressed is through the presence of specific sugars on the surface of our cells. It so happens that many lectins are blood type specific, meaning that they will be attracted to body cells of one blood type and not necessarily those of another. The word lectin comes from the Latin for “to choose”, describing an essential characteristic of these proteins. They choose, according to blood type, the cells that they are going to work on, making them agglutinate. These cells can be red blood cells, white blood cells, cells of the gastrointestinal tract, the pancreas, the kidneys, the liver … but the first cells met by lectins are, of course, those of the digestive tract. That is where they make their first impact. According to researcher Arpad Pusztai, the lectins in our diet have an enormous influence on the way our digestive tract is going to respond to the foods it comes in contact with and this, in turn, affects our health in general. I have noticed that digestive symptoms improve in the first days of following the blood type diet. My patients feel less bloated, have fewer spasms, less nausea, and they find food doesn’t lie as heavy on the stomach.
Dietary lectins can have an effect on different aspects of digestion. They can inactivate certain digestive enzymes and damage the gut wall, thus impairing absorption. This can also lead to substances that would normally remain in the gut leaking through the gut wall into the general circulation – a condition referred to as leaky gut. When the lining of the small intestine cannot act as an efficient barrier any longer bacteria, food antigens capable of triggering an allergic-type reaction in the body, and toxins, can all cross into the bloodstream. Joint inflammation, rheumatoid arthritis and ankylosing spondylitis have all been linked with gut permeability. Lectins can also cause painful inflammation of the gut lining.
It has been found that 5–10 per cent of the lectins in food can pass into the bloodstream and circulate in the body. There they can cause inflammatory reactions such as arthritis and allergies; disrupt thyroid hormone (hypo and hyper thyroidism) and insulin production (diabetes); interfere with the normal function of the nervous system; and settle in the kidneys and the liver, disrupting their function.
The process of digestion can affect lectins in various ways. Lectins are usually not inactivated by gastric acids, meaning they will reach the intestine intact. Chewing can actually aggravate some lectin activity. Cooking also has varying effects on lectins. Certain bean lectins are inactivated by specific soaking and cooking procedures (see instructions on page 188), while the negative aspects of other lectins are increased by cooking (bananas are one example). Interestingly, the lectin contained in wheat – a grain that so many people need to avoid – is inactivated by the process of sprouting.
The main reason for avoiding specific foods on the blood type diet is the presence of lectins. A second reason for avoidance is the responsibility a food may have for the higher incidence of certain health problems in each blood type. For example, blood type A has a higher incidence of cardiovascular disease associated with higher levels of cholesterol. As a protective measure olive oil – which has beneficial effects on cholesterol levels – should be consumed rather than butter. A third reason for avoidance is the internal makeup, the blood group individuality so to speak, that determines which food or food group should be avoided. For example, Os have a problem dealing with milk products and should avoid them almost totally.
Using various laboratory and clinical methods Dr D’Adamo and his team have tested the foods covered in this book and their effects on the body. As the research into blood type diets is an ongoing process it is wise to always seek the latest information. Peter D’Adamo’s website www.dadamo.com is a rich source of information for the layperson, the practitioner and the researcher.
I urge you to read all of the following information, rather than just that on your particular blood type, as some of the health advice is relevant to all types.
the four blood types: food requirements and health characteristics
blood type o: general food recommendations
Humanity’s ancestors were all blood type O. The hunter-gatherers ate what they could find growing or roaming in their environment. Their diet was composed of meat, fish, fowl, leaves, roots, berries, fruits, seeds and nuts. These are, in general, the foods you will do best on if you are blood type O. Eat plenty of vegetables with meat, fish and fowl – your best sources of protein. Include nuts and seeds (particularly linseeds and walnuts) several times a week as these provide extra protein, essential fatty acids and some minerals. Fruit – both dried and fresh – is a good way of satisfying your natural need for something sweet.
Meat, Poultry and Game
Do not worry about eating meat – it is good for you because your body is genetically made to metabolise it. Your digestive system normally has the necessary acids in the stomach and enzymes in the intestines to digest animal protein and fat. However, if you are not accustomed to eating animal protein you may need to gradually introduce meat in small quantities and take digestive enzymes for a while.
Eating meat for you is essential as it will balance your blood sugar levels and help to counteract cravings for carbohydrates. Having good steady energy levels and not making fat from sugar depends on your consumption of animal protein. Maintaining and building good healthy muscle mass also depends on eating animal protein, and this will contribute to your being lean. Choose quality organic meat as often as possible. Red meat is your best protein choice. Avoid pork. A recommendation to eat meat does not mean, however, that you can eat huge amounts of it – have no more 3½–6oz/100–180g of meat or poultry six to eight times a week.
Tamara
Blood Type O
Age 27
I became ill towards the end of 2000. The symptoms were very diffuse (muscle ache, skin rashes), but pointed towards some kind of auto-immune disease. My disease was never properly diagnosed and in the end the doctors bade me farewell without giving me any treatment. At this point I decided to turn to alternative medicine. I should add that for one year prior to my becoming ill, I had been following a vegan diet.
I consulted with Karen, and on her advice I have been eating according to my blood type (O) and taking a variety of supplements for about six months. The effect on my condition has been dramatic. I feel fitter and my energy level has risen. I have experienced an improvement in my sleep patterns and in my daily exercise routine (jogging). The most salient effect has been as a result of giving up wheat flour – I feel a great deal lighter and seem to be digesting other flours (eg. rye and spelt) a lot better. To cut a long story short, I feel light as a feather and healthy.
Seafood
You are the only blood type who can eat virtually all shellfish: oysters, crab, lobster, shrimp, clams etc. Enjoy these whenever you can. Your choice of fish is also large. Fatty fish are especially good for you, as they contain beneficial omega-3 oils that counter inflammation.
Vegetables
All blood types benefit from eating plenty of vegetables. They are the basis of a healthy diet. Ensure they are as fresh as possible and eat them every day for lunch and dinner – raw or cooked, juiced, in salads, in soup – and as a snack. You will find information about the tremendous
