of nuts, seeds, fish, and oils (primarily olive oil). Herbs and spices are generally used in place of salt, and a moderate amount of red wine is consumed with meals. (It must be noted, however, that despite the documented benefits of red wine, alcohol has been shown to increase the risk of certain cancers, so moderation is important.) A recent issue of the New England Journal of Medicine was devoted in large part to articles on the Mediterranean diet for prevention of cardiovascular disease. Moreover, the relationship between adherence to the Mediterranean diet and incidence of cancer was studied in a sample of 25,623 people in Greece. At follow-up almost 8 years later, researchers found that better adherence to the diet was associated with lower overall cancer incidence.5
Key Components of the Plant-Based Mediterranean Diet
• Fruits and vegetables
• Whole grains—breads, pasta, polenta (from corn), bulgur and couscous (from wheat)
• Legumes—beans and lentils
• Seeds and nuts
• Olive oil and other healthy oils
• Fish and poultry
• Red wine once daily
Avoid, or eat rarely, saturated fat from butter, red meat, and eggs. Also avoid deli, luncheon, and cured meats. Eat refined sugars and sweets rarely.
Vegetarian Diets
By definition, a vegetarian diet excludes meat and seafood, emphasizing plant-based foods instead. However, the term “vegetarian” means different things to different people, and as such, vegetarian eating patterns vary widely. Lactoovo-vegetarians avoid only meat and seafood, but will eat other animal foods such as dairy and eggs. Lacto-vegetarians exclude eggs in addition to meat and seafood, but consume dairy. Finally, vegans, or total vegetarians, avoid all animal products including dairy and eggs. Other variations exist as well, such as diets that include fish but are otherwise vegan. All vegetarian diets involve significant consumption of whole grains, vegetables, fruit, and beans, including soy products. People often choose plant-based diets out of concern for the environment, for ethical or philosophical reasons (relating to animal welfare), and, increasingly, for their many health benefits.
As long as they are well planned to ensure adequate nutrition, vegetarian diets can be very healthful. The health advantages include lower cholesterol levels and a decreased risk of heart disease, high blood pressure, and type 2 diabetes. Moreover, vegetarians generally have a lower body mass index (BMI) than their meat-eating counterparts and a lower risk of cancer. Vegetarian diets are low in saturated fat and cholesterol (cholesterol is found only in animal foods) and are rich in dietary fiber, minerals such as magnesium and potassium, vitamins C and E, folate, carotenoids (like beta-carotene/vitamin A), flavonoids, and other beneficial phytochemicals. Many of these nutrients are shown to have cancer-protective properties. Consuming them together in the form of whole foods (as compared to individually in dietary supplements) allows them to act in an additive and synergistic manner, maximizing the benefits.
Plant protein can fulfill protein requirements as well as animal protein can, so long as you consume a variety of plant foods each day in sufficient quantities to meet your caloric needs. Together, whole grains and beans consumed in an approximate two-to-one ratio can supply all of the amino acids we need. Calcium requirements, too, can be met through regular consumption of leafy green vegetables, calcium-fortified plant food such as cereals, soy milk, and rice milk, and/or dairy products. Furthermore, diets high in fruit and vegetables help the body hold on to the calcium it already has. The potassium and magnesium content of fruits and vegetables slows loss of calcium from the bones.
However, vegetarian diets can be low in some important nutrients, particularly vitamin B12 and vitamin D. It should be noted that humans receive only a very small amount of vitamin D from food. Most vitamin D is obtained from sunlight. However, dark skin and use of sun protector creams, necessary to prevent the deadly skin cancer melanoma, also prevent vitamin D from being synthesized by the body. Therefore, many people are vitamin D deficient. It is worth considering taking a vitamin D supplement to avoid vitamin deficiency. Vitamin B12 is found in animal products, including fish, meat, poultry, eggs, milk, and milk products. It is generally not present in plant foods, but fortified breakfast cereals are a readily available source, and supplementation is available.
Vegetarian diets may initially sound dull and boring, but there are many recipes and cookbooks that can help you create attractive, tasty, satisfying, and varied dishes. As more and more people adopt this way of eating, restaurants are increasingly catering to vegetarian and vegan diners as well.
A final note, even those who eat semi-vegetarian diets experience health benefits, so it is not necessary to avoid all animal foods entirely unless you feel inclined to do so.
Dangerous Diets—Some Promoted as Cancer Cures
Macrobiotics
The macrobiotic diet is plant based, comprised largely of whole grains, beans, soups (such as miso soup), and sea vegetables. It excludes meat and dairy, but fish is permitted occasionally. Fruits, nuts, and seeds also are consumed at times, along with vegetable pickles and non-caffeinated teas. More than a diet, however, macrobiotics traditionally encompasses both a philosophy and a way of life. It emphasizes balance in the selection, preparation, and consumption of foods, as well as in day-to-day life.
In a 2009 report, the American Dietetic Association concluded that “appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases.”6 That said, your nutritional needs may vary compared to the average person, which is why it is important to discuss diet with your doctor and/or another nutrition-trained health professional.
Macrobiotic theory is based largely on the yin-yang principle of balance that was integral to ancient Chinese medicine. Yin and yang are seen to be equal but opposite forces that describe all components of life and the universe. The diet and philosophy were initially developed and popularized by Japanese philosopher George Ohsawa in the early twentieth century. An early disciple, Michio Kushi, led the macrobiotic movement from the mid-1900s. The macrobiotic diet was promoted as a cancer cure in the United States for many years, but that effort eventually waned as scientific studies failed to support the claims.
No diet or combination of foods, in fact, has ever been shown to cure cancer. Moreover, practicing macrobiotics and other extreme diets can lead to nutrient deficiencies, such as vitamin B12 and calcium, and inadequate caloric intake.
Gerson Regimen and Metabolic Therapies
Developed in the 1930s by German physician Max Gerson, the Gerson regimen involves a strict metabolic diet, as well as coffee enemas and various supplements intended to aid in detoxifying the body. The diet is vegetarian and emphasizes fresh fruit and vegetable juice; each patient consumes about 20 pounds of fruits and vegetables each day, largely in the form of fresh juice. Supplemental digestive enzymes are frequently given, as well as coffee enemas, which are claimed to stimulate the excretion of bile from the liver and eliminate toxins from the body. This and many other extreme diets are based on the incorrect idea that cancer is caused by a buildup of toxins in the body, and that detoxification will cure the disease. The Gerson clinic advertises its cancer therapy as “a
