Source: Web exclusive, May 2008
Here’s something you should know up front: ‘There is no one magic food for fertility,’ says Susie Langley, a Toronto-based registered dietitian and nutrition consultant who specializes in infertility. But don’t be discouraged. Dr. Jorge Chavarro and Dr. Walter Willett of the Harvard School of Public Health and Patrick Skerrett, editor of the Harvard Heart Letter, have put together an eating strategy in their new book, The Fertility Diet, to help tip the scales in your favour. Here’s what they suggest you try:
Brown rice, oatmeal, barley, whole grain cereal
Reach for whole grain foods because they are ‘slow carbs’ that have a gradual effect on insulin, as opposed to highly refined carbs (cakes, pizza, pastries, chips, white rice, etc.), which cause insulin to spike. When insulin rises too high, it disrupts the finely tuned balance of hormones needed for reproduction. Women who have polycystic ovary syndrome (PCOS), the single most common cause of ovulatory infertility, benefit especially from slow carbs because they usually have insulin resistance. ‘Since their muscles don’t respond as readily to insulin’s ‘open up for sugar’ signal, their bodies must make more and more insulin, resulting in higher insulin levels,’ Skerrett explains.
Breakfast: Muesli or oatmeal.
Lunch: Sandwich on whole wheat bread or whole wheat pita.
Dinner: Semolina/whole wheat pasta, brown rice, quinoa.
Olive oil, Canola oil, peanut oil, cashews, almonds, pumpkin and sesame seeds
Not all fats are bad, as was once thought. Monounsaturated fats, found in the oils, nuts and seeds listed above, improve the body’s sensitivity to insulin and ease inflammation, providing a boost to fertility. On the other hand, trans fats are bad for fertility. They increase inflammation throughout the body and quash the activation of PPAR-gamma (receptors that switch on insulin sensitivity), which means higher blood sugar and insulin levels. Both factors interfere with ovulation, conception and early embryonic development, says Skerrett.
Daily target: 22 to 27 grams (10 to 15 percent of calories of a daily 2,000-calorie diet.)
Salmon, chunk light tuna, mackerel, sardines, soybeans
Polyunsaturated fats, which contain Omega-3 fatty acids, can be found in deep-coloured fish and soy food. Those aiming for motherhood need Omega-3s in their diet because they regulate what goes in and out of cells and produce hormones that increase blood flow to the uterus, increasing your chances of pregnancy. ‘Omega-3 fatty acids are important for brain and eyesight development of the fetus and the infant. They may be helpful for bringing the pregnancy to term as well,’ says Langley. Just check with your public health department about mercury levels if you’re planning to eat freshwater fish caught in your province.
Daily target: 17 to 22 grams (8 to 10 percent of calories of 2,000-calorie diet.)
Whole milk, full-fat yogurt, ice cream
Finally’justification to enjoy that bowl of ice cream! Whole milk and foods made from whole milk are better for fertility than skim milk, according to The Fertility Diet. Why? Whole milk contains male and female hormones. Female hormones attach to fat globules in milk. Skimming off milk fat removes the female hormones, while leaving male hormones behinnd. At the same time, whey proteins are often added to skim milk to make it look creamier, and some of those proteins have androgenic [male hormone] properties. These changes result in an excess of male hormones that can tip the scales against ovulation and conception, Skerrett explains. An excess of male hormones can prevent follicles from maturing. This isn’t a license to go wild. You shouldn’t eat a tub of Haagen-Dazs. Still, Langley advises, ‘Go ahead and have that bowl of ice cream if you’re underweight and need more calories, but go easy if you’re overweight.’
Daily target: Three servings of milk or alternatives every day (one serving is 1 cup of whole milk, 175 grams full-fat yogurt or 50 grams of cheese).
Spinach, beans, pumpkin seeds, lentils, oranges, strawberries
Folic acid and iron both affect fertility. Folic acid is a vital part of building DNA and converting some amino acids into others. So eating foods high in folic acid, such as spinach, beans, oranges, strawberries and lentils, may influence the start of a pregnancy and its continuation, as well as help prevent neural tube defects, according to The Fertility Diet. With regard to iron, the egg needs iron to provide the energy to power the DNA and protein synthesis required for fertilization. Again, plant foods high in iron, including spinach, legumes, and nuts and seeds, are beneficial for those who eat a more plant-based diet.
The Fertility Diet doesn’t promote red meat as a source of iron because, Skerrett explains, the body doesn’t regulate the storage of iron from meat as carefully as it does from plant-based sources or supplements. Langley isn’t comfortable with this recommendation. First, it won’t suit a carnivore’s eating style. Iron is most abundant in lean red meat, dark meat on poultry, fish and seafood and is more readily absorbed by the body. So, unless you eat a lot of plant-based foods high in iron, you might come up short.
Because it’s often difficult to get enough folate and iron through diet alone, your doctor may advise you to take prenatal supplements for extra folate and iron at least three months in advance of planning a pregnancy. It would be wise to have your iron checked by your doctor if you are a vegetarian or avoid red meat in order to find out if you need a therapeutic dose of iron, says Langley.
Daily target: 700 mcg daily of folic acid and 40 to 80 milligrams of iron a day.
Water, not alcohol
Water keeps you hydrated, which is important for general good health and fertility. But pull back on the booze. A study in Stockholm of more than 7,000 women between 18 and 28 examined alcohol consumption and infertility, and it was the high-alcohol consumers that went for infertility exams at hospitals. A study conducted at M.G.R. Medical University India discovered that chronic alcohol consumption decreased semen volume, sperm count, motility and the number of normal sperm.
Energy balance for fertility
Finally, you want to take energy balance into account. The amount of energy you take in through your diet (the number of calories you eat) should be equal to the amount of energy you expend in a day, according to Langley. If you eat too little or exercise too much, you could end up with a negative energy balance, meaning your body weight may be too low’leading to poor fertility and inability to conceive. On the other hand, eating too much or exercising too little may lead to positive energy balance and weight gain’which is also associated with poor fertility.
Found this article informative? Subscribe to our magazine today and receive more Best Health exclusives delivered to your door!