The study found that the type of carbohydrates you eat has a significant influence on fertility. It found that diets high in refined and easily digested carbohydrates increased the odds of ovulatory infertility. Fast carbohydrates (high GI foods) bring a quick influx of glucose into the blood stream which then leads to a rapid rise in insulin. This is often associated with a quick energy high followed by a depressing low. Fast carbs include foods made with white flour and refined sugar, russet potatoes, alcohol, candy, cookies, pastries, doughnuts, chips, and sodas. On the other hand, diets that were rich in high fibre and slow carbohydrates (low GI foods) were associated with improved fertility. Low GI foods include whole grains, brown rice, legumes, and vegetables. This lines-up nicely with work showing that a diet rich in these slow carbs and fibre before pregnancy helps prevent gestational diabetes, an increasingly common problem for pregnant women and their babies.
Carbohydrates are the primary determinant of blood sugar and insulin levels. Fats and protein are digested slowly and do not have much impact on blood sugar by themselves. When blood sugar and insulin levels rise too high, they disrupt ovulation.
In fact, the study found that the amount of carbohydrates in the diet was as important as the type. Women whose diet contained at least 60% calories from slow carbohydrates tended to be a healthier weight than women who generally avoided carbs. The slow carb eaters tended to also have an overall healthier lifestyle including more exercise, less alcohol and coffee, less fat and animal protein, and more plant protein.
What is insulin resistance?
Insulin resistance refers to the body’s reduced capacity to metabolize insulin and glucose. The pancreas works harder and harder to produce insulin, but the insulin cannot do its work of transporting glucose (sugar) into the cells because of a hormonal imbalance or because a person is overweight. The excess insulin in the blood leads to excess glucose in the blood and contributes to prediabetes, weight gain, and diabesity
What is diabesity?
Diabesity refers to Type 2 diabetes caused by obesity and insulin resistance.
What is the glycemic index?
The glycemic index (GI) is a measure of how high the blood sugar rises after eating a food. The foods are ranked on a scale, using white table sugar as a comparison (ranked as 100). Low GI foods cause a lower rise in blood sugar after a meal, creating longer satiety, less blood sugar swings and sustained energy. Research is pointing to a connection between low GI foods and increased physical performance, better weight management, prevention and treatment of diabetes, and mood stability.
Fertility Diet Recommendations:
You can improve ovulation with a diet based on at least 60% of calories from slow release carbohydrates such as whole grains, dried beans and peas, vegetables, and whole fruits. Eat mostly low and medium GI foods, and avoid those foods with a high GI.
Examples of GI of Common Foods
Low GI = 55 or less
- Sprouted grain bread/tortillas
- Sweet potatoes
- Oat bran, pumpernickel, or buckwheat bread
- Al dente (firm) pasta
- Quinoa, bulgur, barley
- Bran Buds with Psyllium™
- Fruits and vegetables
- Whole milk
Medium GI = 56 – 69
- Potatoes (new or red)
- Split pea or green pea soup
- Brown rice
- Basmati rice
- Shredded Wheat cereal
- Whole grain bread
- Rye bread/Ryvita™ crackers
High GI = 70 or more
- Instant mashed potatoes
- Potato, baking (russet)
- White and instant rice
- Whole wheat flour bread
- Pancakes, waffles
- Most breakfast cereals
- Soda crackers
- French fries
- Energy bars
- Most granola bars
- Sports drinks
The GI of a meal can be lowered by adding:
- Lemon juice or vinegar; add broccoli with lemon juice or a salad with dressing to a meal with high or medium GI foods i.e. brown rice
- Healthy fats such as olive oil, walnut oil or organic butter
- Mixing low GI food with a medium/high GI food (eg. beans and brown basmati rice)
Here are some examples:
- Breakfast: free-range eggs, sprouted whole grain toast or steel cut oatmeal with nuts and blueberrie
- Lunch: salmon on sprouted tortilla, salad with oil and lemon juice
- Dinner: bean or vegetable chili over brown rice, fresh whole fruit salad
For a complete listing of the glycemic index or more foods, see www.glycemicindex.com.
Don’t get too lost in the glycemic index. The important part is to focus on eating more legumes, whole grains, and vegetables in place of fruit, juice, or processed grains (breads, muffins, cakes, cookies).
What are Whole Grains?
Whole grains are plant foods that include all parts of the grain kernel: the bran, germ, and endosperm. Whole grains contain the most nutrients, including B vitamins, magnesium, chromium and fibre. They take longer to cook but are worth it for their flavour, texture and nutrition. These are the best source of complex "slow" carbohydrates as they are high in fibre, enzymes, antioxidants, vitamins and minerals. Eat a few servings of whole grains every day, depending on your energy requirements.
Refined grains are whole grains that have been processed to remove part of the bran, germ or endosperm. The more a whole grain is refined during processing, the more nutrients are lost. Some are partly refined like whole wheat flour, bulgur and couscous. These can be eaten occasionally, however should be avoided by women with PCOS and/or if you are trying to lose weight.
Processed grains have been totally refined or processed to the point where there is very little nutrition left (white rice, white flour). Some refined grains have had nutrients added back to them after processing (enriched white bread). Avoid these foods while you are following the Fertility Diet.
PCOS clients should restrict the amount of flour products they eat. Sprouted wheat or grains are a better choice as even whole wheat flour is processed and quickly digested and can cause rapid increase in blood sugar. To slow down the rate that foods made with flour are absorbed you can combine them with healthy fats (like almond or peanut butter) or protein.
True whole grains are barley, large oats, brown rice, amaranth, quinoa, millet, wheat berries, spelt berries, and kamut berries.