by Nicole Holovach, MS, RD, LDN
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder
in women. Typical symptoms include hirsutism, menstrual irregularity,
and infertility. Furthermore, PCOS predisposes women to metabolic dysfunction,
overweight and obesity, and an increased risk of type 2 diabetes. Obesity
exacerbates the insulin resistance that is a feature of PCOS in many women.
Reducing insulin levels and improving insulin sensitivity are an essential
part of treatment and management.
Diet plays a significant role in the regulation of blood sugar and insulin
levels. Low-glycemic index diets are currently popular with both registered
dietitians and patients in the management of PCOS.
The glycemic index is a rating of how much a food is going to potentially
raise your blood sugar levels. Glycemic load in another rating that was
basically created to address one of the shortcomings of glycemic index,
which is it doesn’t take serving size into account. So watermelon
is high on the glycemic index, but the amount of carbohydrates in a general
serving size of watermelon is pretty low.
I have a confession to make: I’ve never loved the glycemic index.
Even in my initial days of nutrition counseling years ago when it was
first getting popular, it seemed rather arbitrary. Of course whole foods
like vegetables, fruits, and legumes would be better for a person’s
blood sugar control than refined and processed foods like bagels, crackers,
cookies, cakes, doughnuts, croissants, waffles, and most packaged breakfast
cereals! And I still resent the fact that the glycemic index has just
about destroyed the reputation of healthy, nutrient-dense foods like carrots,
watermelon, bananas, and white potatoes.
But, my biggest *issue* with the glycemic index is that the glycemic index
of a particular food can be influenced by what it is eaten with. Food
is rarely eaten in isolation, rather as part of a meal. A white potato,
combined with protein and fat, has a much lower effect on your blood sugar
than a potato alone. Who eats a potato by itself? Foods like bananas that
you might grab and go, can be made even healthier by combining with fat
or protein, like almond butter or yogurt. Also, the way a food is cooked
affects its rating on the glycemic index. Al dente pasta has a lower rating
on the glycemic index than pasta that is cooked longer.
Although the research is generally not supportive of either glycemic index
or glycemic load for weight loss, insulin, or blood sugar control, it
continues to be popular in forums and among health professionals in the
management of PCOS. Instead of having patients memorize a list of random
foods, I’d much rather focus on having them plan regular meals and
snacks with a healthy balance of carbohydrates, protein, and fat for blood
sugar control. And also focus on the myriad of other things that can improve
insulin sensitivity like sleep, stress, and physical activity.