To understand why the McDougall Program is such powerful medicine, you must start by recognizing that plant foods are the most abundant sources of nutrition on earth. Nutrients are the raw materials your body needs to function properly and can generally be split into two types – the ones your body can make by itself and the ones it can derive only from your food. The latter are called “essential” nutrients.
There are 13 essential vitamins. Eleven are made in abundance by plants. The two that are not produced by plants are vitamins D and B12, both of which are stored in your tissues for long periods of time. You’ll get enough vitamin D with adequate exposure to sunlight and B12 can be easily supplemented. I tell pregnant and nursing women, and people who follow my diet strictly for more than 3 years, to take five micrograms of vitamin B12 daily.
There’s no comparison between animal foods and plant foods when it comes to providing immune-boosting and cancer-fighting nutrients. Animal foods are either exceedingly low or devoid of antioxidants and tend to offer concentrated amounts of individual nutrients, like protein or calcium, while being deficient in many others. By contrast, plant foods are rich in antioxidants and provide a wide spectrum of vitamins, minerals, and other health-promoting nutrients.
Only plants contain powerful substances called phytochemicals, which scientists are now discovering protect us from cancer, heart disease, and an array of other serious illnesses. Plants are also the primary source of all minerals in our diet. Minerals are derived from the earth and make their way into the food supply via plants. The only reason animal foods contain any minerals at all is because the animals eat plants, or they eat animals that eat plants. And plants offer our only sources of dietary fiber, which binds in our intestines with fat, cholesterol, environmental pollutants and disease-causing hormones to eliminate these dangers from the body. Fiber also decreases intestinal transit time and promotes healthy bowel elimination.
Plant foods contain generous amounts of calcium. A cup of cooked collard greens contains about 360 mg of calcium, while a cup of milk contains about 300 mg. A cup of cooked kale contains 210 mg. There is NO disorder known as “dietary calcium deficiency” – in other words, there is plenty of calcium in all plant food diets to meet the needs of both children and adults alike. Osteoporosis is not a disease that results from too little calcium, but primarily from acids derived from too much animal protein that rob the body of calcium and thus weaken bones. A diet based on starches with a plentiful supply of fruits and vegetables, combined with modest exercise, will preserve skeletal strength and even regain lost bone mass.
Protein is extremely misunderstood. First, you should know that plants contain protein and all of the essential amino acids needed to build it. Second, animal foods are not necessary to get the protein your body needs – indeed, all the protein you need and more can be easily derived from plant foods alone.
The World Health Organization (WHO) recommends men, women, and children get five percent of their calories from protein. The chart below reveals the protein levels of selected plants and as you can see it’s virtually impossible to fail to meet the WHO’s daily requirements.
|Percentage of calories derived from protein|
Americans consume 6 to 10 times as much protein as they need. All that excess protein overworks the liver and kidneys causing both to become enlarged and injured. Excess protein consumption also causes the kidneys to pull large quantities of calcium from the body, causing bones to weaken and kidney stones to form.
Scientists have found that animal proteins are particularly damaging to the body because so many of their amino acids contain sulfa, which is far more toxic to the liver and kidneys than vegetable proteins. One of the most time-honored approaches to healing the kidneys and liver, in fact, is to eat a low-protein diet, especially a diet low in animal proteins. When the protein content of the diet drops, kidneys are strengthened and very often healed.
Carbohydrates are our primary source of energy. They alone provide energy for red blood cells, and certain cells of the kidneys, and they’re the preferred fuel for the central nervous system, including the brain. Fat, on the other hand, is a secondary source of energy that can be used by some tissues, such as muscle, but is more often stored for use in times of famine.
Humans were designed by nature to crave carbohydrates. With their unique combination of sweet flavor, energy and nutrition, carbohydrates regulate our hunger drive. There are no carbohydrates in red meat, poultry, fish, shellfish, or eggs, and most dairy products contain little if any. Cheese, for example, contains only two percent. This is an important reason why people who eat a diet rich in animal foods rarely feel satisfied and become compulsive overeaters. Unless you eat enough carbohydrate foods, you’ll remain hungry and crave more food.
Unprocessed plant foods like brown rice, potatoes, squash, broccoli, and apples (just to name a few) are loaded with complex carbohydrates – long chains of sugars that must be broken down inside your intestine before they can be used as fuel. The process of digesting these complex carbohydrates is slow and methodical, providing a steady stream of fuel pumped into your bloodstream as long-lasting energy. On the McDougall diet, 70% – 90% percent of your calories are derived from complex carbohydrates, providing you with all the nutrients you need for optimum health, plus a high level of vitality and endurance.