PCOS, or polycystic ovarian syndrome, is the most common hormonal disorder in women of reproductive age. Symptoms of PCOS include:
- Irregular menstrual cycles
- High androgen(Male sex hormone) levels
- The development of cysts that rupture and cause pain
Aside from the painful cyst ruptures, PCOS also negatively affects a woman’s fertility. It’s more common in women who are obese because insulin resistance is a cause. However, lean women have higher insulin levels than those without it. And lean women with PCOS are more likely to develop insulin resistance than those without it.
Research identified one of the main ways that insulin resistance causes PCOS. When insulin levels increase, the ovaries produce too much testosterone. This is from increased activity of the enzyme cytochrome P450c17a, which increases androgen production in the ovaries. Knowing this is great because insulin resistance is quite easy to treat.
The easiest way to improve insulin resistance is to lose weight if you’re obese. That’s easy enough to say, but putting that plan in to action is quite difficult for most. Also, lean women with PCOS don’t have that luxury, which makes it more difficult to treat.
Thus, we should identify ways to treat PCOS that don’t involve weight loss.
Circadian rhythms and insulin resistance
Circadian rhythms are variations in our physiology that follow a 24 hour pattern. These patterns are dictated by our behavior through exposure to environmental patterns called time-givers(zeitgebers). Many hormones follow a circadian rhythm, including insulin. Fertility also follows a circadian rhythm.
In fact, a recent study identified insulin as the primary time-giver that identifies when we eat. I covered this in a recent blog called Fix insulin resistance, fix leaky gut. Insulin resistance causes circadian disruption which can disrupt a woman’s hormones and menstrual cycle.
But the converse is also true: circadian disruption causes insulin resistance. So correcting behaviors that lead to insulin resistance can treat PCOS. With this in mind, let’s look at a study addressing this.
Proper circadian meal patterns corrects PCOS in lean women
A study in 2013 looked at meal timing and size as a way to combat PCOS. They took 2 groups of lean women with PCOS and fed them 1800 calories a day for 90 days. They ate the exact same foods and total calories, the only difference being how much they ate at each meal.
In one group, calories for each meal were 968/640/190 for breakfast/lunch/dinner. In the other group, calories for each meal were 190/640/968. Glucose, insulin, androgens, and ovulation were compared between the groups throughout 90 days.
Both groups were similar in all measured factors at the beginning of the study. But there were large difference between the groups after 90 days. Beneficial changes occurred in the big breakfast group but not the big dinner group.
In the big breakfast group, glucose and insulin levels dropped by 7% and 54% during an oral glucose tolerance test, respectively. In other words, they were less insulin resistant. The big dinner group saw no change in these measures.
Free testosterone dropped by 50% and sex hormone binding globulin(SHBG) doubled in the big breakfast group. SHBG binds excess estrogen, testosterone and dihydroxytestosterone(DHT). There was also a reduction in total androgen levels, which was due to decreased cytochrome P450c17a activity.
During the first 4 weeks, no women from either group ovulated. From week 5 on, women ovulated in both groups. During month 3, 50% of the women in the breakfast group ovulated compared to 20% in the dinner group. Interestingly, only women in the breakfast group experienced more than 1 ovulation during the study.
Circadian rhythms and PCOS
The researchers theorized that the beneficial effects of a bigger breakfast were due to optimizing circadian rhythms. Humans have higher insulin sensitivity and metabolize energy more efficiently in the morning than at night.
Taking it a step further, recent evidence shows that eating at night causes several problems. Women who ate 968 cals at dinner likely metabolized that meal well in to their sleep period. About 2-3 hours before we fall sleep, we begin secreting the hormone melatonin.
Melatonin inhibits insulin secretion and restores insulin sensitivity the next day. In fact, a new review recently published is titled: Melatonin signaling a key regulator of glucose homeostasis and energy metabolsim.
Consuming food close to when we sleep causes blood glucose to elevate and can impair insulin sensitivity the next day. Thus, it’s not recommended to consume food within 3 hours of bedtime. The subjects in this study weren’t told this, which could have altered the results.
Other studies show that genetic differences in the melatonin receptor predispose people to Type 2 diabetes. Women with PCOS may also have this genetic difference. It certainly makes sense given their increased risk of insulin resistance/Type 2 diabetes.
The substantial changes in this study indicate that optimizing circadian rhythms is a powerful intervention to reverse PCOS. The most incredible aspect of the study is that they only addressed part of one time-giver. They didn’t address:
- Light exposure
- Physical activity
- The length of the feeding window
There’s no telling how much better the results could have been if they addressed all of these factors. I suspect more women would have ovulated had they addressed all of these factors. Working on all of them may also help overweight women with PCOS give birth.
Have PCOS and need help getting all of these circadian factors under control? There’s a program for that, designed specifically to address insulin resistance with principles of circadian rhythms. It’s called the Reverse Type 2 Diabetes Circadian Bundle and is for sale in our new store. Check out the program here: