Book Review

The scientific study of nutrition is relatively new with increasing research results reported over the last two decades.  The food pyramid we are encouraged to look to as a guide for daily food choices was last updated in 1992 by the U.S. Department of Agriculture (USDA).  Dr. Charles Willett, Head of Harvard University's Department of Nutrition and a member of Harvard's medical school faculty, notes that while its pyramid has been eroded by research from across the globe, the USDA has failed to make changes needed to address issues of obesity, poor health, and unnecessary early death.  Dr. Willett responded in Eat, Drink and Be Healthy with his Healthy Eating Pyramid based on evidence from many research studies.  He projects the need to adjust it over time as new evidence is discovered.  Willett also recognizes that other food pyramids, such as the Asian, Latin, Mediterranean and vegetarian, are good evidence-based guides for healthy eating.  His Healthy Eating Pyramid offers a broad guide that is not based on a specific culture, but which is informed by the best in other traditions.

            The USDA Pyramid and the Healthy Eating Pyramid share an emphasis on vegetables and fruits, but otherwise they differ greatly.  The base of the Healthy Eating Pyramid contrasts dramatically with the USDA's base guide to consume eight to eleven daily servings of bread, cereal, rice and pasta products; its base advice is daily exercise and weight control necessary for long-term health.  Another striking difference is the role of healthy fats in the foundation of the Healthy Eating Pyramid while USDA advises that all fats be used sparingly.  Willett encourages eating fewer bad (saturated and trans) fats and more good (unsaturated) fats from nuts, seeds, grains, fish, and such liquid oils as olive, canola, soybean, corn, sunflower, peanut, and other vegetable oils.

            The Healthy Eating Pyramid urges the eating of fewer refined-grain carbohydrates and more whole-grain carbohydrates which digest slowly and offer protection against diabetes, heart disease, cancer and gastrointestinal problems such as diverticulosis and constipation.  It encourages the choice of healthier sources of protein, using less red meat and more beans, nuts, fish poultry and eggs (yes, real eggs).  Attention is given to vegetable sources of protein for those who want to follow a vegetarian diet.

            While Willett urges the eating of plenty of vegetables and fruits, he encourages Americans to rethink their love affair with the potato, which should be used sparingly because it negatively impacts blood sugar and insulin levels.  A diet rich in vegetables and fruits lowers blood pressure, decreases chances for heart attack and stroke, protects against a variety of cancers, guards against constipation and other gastrointestinal problems, and limits chances for developing age-related problems like cataracts and macular degeneration.

            Willett’s pyramid recognizes that moderate alcohol consumption cuts the risk of heart attack, heart disease, and clot-caused stroke.  Finally Willett encourages the use of a daily multivitamin for insurance.

            Research evidence in support of each Healthy Eating Pyramid element is presented in a separate easy to follow chapter.  Of special interest to those who have PXE is an added chapter on calcium, whose need, Willett says, is grossly, perhaps dangerously, overstated for Americans.  Calcium intake with related fractures vary greatly in different countries from a low average of 300 mg. per day in India, Japan and Peru to a high average of 1,300 mg. per day in Finland and other Scandinavian countries.  Countries with the highest average calcium intake tend to have higher, not lower, hip fracture rates.  Differences in physical activity levels, sunlight, and other dietary factors complicate our understanding of the calcium/fracture relationship.  Vitamins D and K and sex hormones also play roles in this process.  Studies indicate that about 550 mg. of calcium is an optimal level for the mythical average adult.  Selecting one's source of calcium is an important decision.  Dairy products are associated with heightened levels of ovarian cancer in women and prostate cancer in men.  Protein plays a role by leaching calcium from bone as calcium is used by the body to neutralize acids released into the blood stream when protein is digested.  Willett concedes that as we are still learning about the need for calcium individuals should make consumption decisions with a trusted health care professional.  But, he adds, almost everyone can reduce the chance of developing osteoporosis by engaging in physical activities to keep bones and muscles strong, by getting enough vitamin K through the eating of at least one serving a day of green leafy vegetables, and by taking a daily multivitamin containing vitamin D.  Willett's advice confirms that of Dr. Kenneth Neldner that those with PXE can safety lower their calcium consumption.

            The book's final chapter includes fifty recipes with menus for one week to illustrate how to put into practice the principles given in the preceding chapters.  Variations with each recipe address needs of those with diabetes, high blood pressure, high cholesterol, and those who are pregnant or who need to lose weight.  The recipes are planned to demonstrate that healthy eating need not be complicated or boring. They celebrate whole grains, fresh produce and healthy fats.  And finally, general tips are included to improve the quality of meals with suggestions for healthful snacking.

            This book so strongly supports advice many of us have received from Kenneth Neldner, M.D. (see his The Nature and the Nurture of PXE in this issue) that it may prove helpful for those with PXE who are seeking detailed dietary guidance.  It also is interesting, even fun to read.