Continuing with PCOS awareness month this September, let’s talk supplements. If you search “PCOS supplements” on Google, you’ll get over 10 million results. There are dozens of supplements and herbal remedies that claim to reduce PCOS symptoms. Unfortunately, there isn’t all that much research out there specifically looking at whether individual supplements affect PCOS symptoms. Here’s five supplements that are often recommended for PCOS, and a review of some of the evidence behind them.
Remember to speak to your doctor or healthcare provider before starting any new supplements.
Inositol is part of the wider family of B vitamins, which can improve insulin sensitivity (1). Of all supplements, inositol probably has some of the best evidence behind it for PCOS management. Even then, WebMD only describes it as “possibly effective”(2). Many inositol supplements come in the D-chiro inositol form. There is also evidence to suggest that a 40:1 ratio of myo-inositol to D-chiro inositol may be best for supporting egg maturation and release in the ovaries (3).
In the UK, it is currently recommended that vitamin D should be supplemented during the winter months, or year-round for people with darker skin tones, who cover up more, or who stay inside most of the day. So regardless of PCOS, you probably should be taking vitamin D for at least part of the year. On top of this, vitamin D deficiency is more common in people with PCOS. Studies on the link between PCOS and vitamin D are inconsistent, however. Vitamin D may help to reduce insulin resistance (4) and support egg maturation and release (5).
Studies indicate that women with PCOS tend to have lower zinc levels. Zinc deficiency is linked to type 2 diabetes, higher body weights, and poor blood glucose control. Supplementation may help with blood glucose levels, and to reduce risk of developing type 2 diabetes (6). Zinc levels may be sufficient from dietary sources without the need for supplementation, so check with your doctor or registered nutritionist/dietitian first.
Omega 3 polyunsaturated fatty acids are an essential part of the diet and are associated with reduced cardiovascular disease (CVD) risk and lower circulating triglyceride levels. Findings in studies have been inconsistent, although certain blood markers (e.g. glucose, testosterone, LDL, ApoB and cholesterol) showed improvement in some of these studies (7-9). Sources of omega 3s include oily fish and certain nuts and seeds such as flaxseeds. They can be supplemented via fish oil-based capsules, or algal-based.
Trials on cinnamon for PCOS have included supplements, extracts and group cinnamon. One trial found evidence that regularity of menstrual cycles improved over six months alongside cinnamon supplementation (10). Other studies indicate that cinnamon may help with insulin sensitivity (11-12). The extent to which cinnamon had an effect varied in studies. Around 1.5g per day of ground cinnamon (or supplement equivalent) may be sufficient to have a benefit on cycle regularity and insulin resistance.