Newsweek article on fertility

An informative article written by Jorge E. Chavarro, MD, Walter Willett, MD, and Patrick Skerrett appeared in the December 10th issue of Newsweek. It has some very positive comments on the importance of diet, exercise, and weight control in fertility. However, i completely disagree with their comments on protein.

Highlights

• The linked epidemics of obesity and diabetes sweeping the country have reproductive repercussions. Environmental contaminants known as endocrine disruptors, such as some pesticides and emissions from burning plastics, appear to affect fertility in women and men. Stress and anxiety, both in general and about fertility, can also interfere with getting pregnant.
  
  
• 18,000 women have taken part in the Nurses' Health Study, a long-term research project looking at the effects of diet and other factors on the development of chronic conditions such as heart disease, cancer and other diseases. Each of these women said she was trying to have a baby. Over eight years of follow-up, most of them did. About one in six women, though, had some trouble getting pregnant, including hundreds who experienced ovulatory infertility. When we compared their diets, exercise habits and other lifestyle choices with those of women who readily got pregnant, several key differences emerged.
  
  
• Ovulatory infertility, which accounts for one quarter or more of all cases of infertility.
  
  
• New research from the Nurses' Health Study shows that carbohydrate choices also influence fertility. Eating lots of easily digested carbohydrates (fast carbs), such as white bread, potatoes and sugared sodas, increases the odds that you'll find yourself struggling with ovulatory infertility. Choosing slowly digested carbohydrates that are rich in fiber can improve fertility.
  
  
• Blood-sugar and insulin levels - when these rise too high, as they do in millions of individuals with insulin resistance, they disrupt the finely tuned balance of hormones needed for reproduction. The ensuing hormonal changes throw ovulation off-kilter.
  
  
• Glycemic load - this relatively new measure conveys information about both the amount of carbohydrate in the diet and how quickly it is turned to blood sugar. Women in the highest glycemic-load category were 92 percent more likely to have had ovulatory infertility than women in the lowest category. In general, cold breakfast cereals, white rice and potatoes were linked with a higher risk of ovulatory infertility.
  
  
• Adding more carbohydrates at the expense of naturally occurring fats predicted a decrease in fertility. This could very well mean that natural fats, especially unsaturated fats, improve ovulation when they replace easily digested carbohydrates.
  
  
• Eating whole grains, beans, vegetables and whole fruits—all of which are good sources of slowly digested carbohydrates—can improve ovulation and your chances of getting pregnant.
  
  
• Trans fats are a powerful deterrent to ovulation and conception. Eating less of this artificial fat can improve fertility, and simultaneously adding in healthful unsaturated fats whenever possible can boost it even further. Across the board, the more trans fat in the diet, the greater the likelihood of developing ovulatory infertility. We saw an effect even at daily trans fat intakes of about four grams a day. That's less than the amount the average American gets each day.
  
  
• Women, their midwives and doctors, and fertility researchers have known for ages that body fat and energy stores affect reproduction. Women who don't have enough stored energy to sustain a pregnancy often have trouble ovulating or stop menstruating altogether. Women who have too much stored energy often have difficulty conceiving for other reasons, many of which affect ovulation.
  
  
• A daily serving or two of whole milk and foods made from whole milk—full-fat yogurt, cottage cheese—seem to offer some protection against ovulatory infertility, while skim and low-fat milk do the opposite.
  
  
• Weighing too much or too little can interrupt normal menstrual cycles, throw off ovulation or stop it altogether. Excess weight lowers the odds that in vitro fertilization or other assisted reproductive technologies will succeed. Women with the lowest and highest Body Mass Indexes (BMI) were more likely to have had trouble with ovulatory infertility than women in the middle.
  
  
• Too much blood sugar and insulin in the bloodstream, it endangers ovulation, conception and pregnancy. Physical activity and exercise are recommended and even prescribed for almost everyone—except women who are having trouble getting pregnant.
  
  
• Being in the fertility zone means you aren't overdoing or underdoing exercise. For most women, this means getting at least 30 minutes of exercise every day. Results from the Nurses' Health Study support this evolutionary perspective and show that exercise, particularly vigorous exercise, actually improves fertility. Exercising for at least 30 minutes on most days of the week is a great place to start.
  

Lowlights

• The Protein Factor
  
  At the center of most dinner plates sits, to put it bluntly, a hunk of protein. Beef, chicken and pork are Americans' favorites, trailed by fish. Beans lag far, far behind. That's too bad. Beans are an excellent source of protein and other needed nutrients, like fiber and many minerals. And by promoting the lowly bean from side dish to center stage and becoming more inventive with protein-rich nuts, you might find yourself eating for two. Findings from the Nurses' Health Study indicate that getting more protein from plants and less from animals is another big step toward walking away from ovulatory infertility.
  
  Scattered hints in the medical literature that protein in the diet may influence blood sugar, sensitivity to insulin and the production of insulin-like growth factor-1—all of which play important roles in ovulation—prompted us to look at protein's impact on ovulatory infertility in the Nurses' Health Study.
  
  We grouped the participants by their average daily protein intake. The lowest-protein group took in an average of 77 grams a day; the highest, an average of 115 grams. After factoring in smoking, fat intake, weight and other things that can affect fertility, we found that women in the highest-protein group were 41 percent more likely to have reported problems with ovulatory infertility than women in the lowest-protein group.
  
  When we looked at animal protein intake separately from plant protein, an interesting distinction appeared. Ovulatory infertility was 39 percent more likely in women with the highest intake of animal protein than in those with the lowest. The reverse was true for women with the highest intake of plant protein, who were substantially less likely to have had ovulatory infertility than women with the lowest plant protein intake.
  
  That's the big picture. Computer models helped refine these relationships and put them in perspective. When total calories were kept constant, adding one serving a day of red meat, chicken or turkey predicted nearly a one-third increase in the risk of ovulatory infertility. And while adding one serving a day of fish or eggs didn't influence ovulatory infertility, adding one serving a day of beans, peas, tofu or soybeans, peanuts or other nuts predicted modest protection against ovulatory infertility.
  
  Eating more of one thing means eating less of another, if you want to keep your weight stable. We modeled the effect that juggling the proportions of protein and carbohydrate would have on fertility. Adding animal protein instead of carbohydrate was related to a greater risk of ovulatory infertility. Swapping 25 grams of animal protein for 25 grams of carbohydrates upped the risk by nearly 20 percent. Adding plant protein instead of carbohydrates was related to a lower risk of ovulatory infertility. Swapping 25 grams of plant protein for 25 grams of carbohydrates shrank the risk by 43 percent. Adding plant protein instead of animal protein was even more effective. Replacing 25 grams of animal protein with 25 grams of plant protein was related to a 50 percent lower risk of ovulatory infertility.
  
  These results point the way to another strategy for overcoming ovulatory infertility—eating more protein from plants and less from animals. They also add to the small but growing body of evidence that plant protein is somehow different from animal protein.

Bonnie comment - Soybeans and peanuts are awful for pregnancy. I suspect that when they looked at animal protein in these subjects, the protein was not organic, free-range, or antibiotic/hormone-free, which makes a huge difference. Animal protein is essential for pregnancy.

The full article can be accessed below.

http://www.newsweek.com/id/73354