Bilberry in pregnancy and breastfeeding

What NCCIH says about safety

Bilberry fruit is considered safe when consumed in amounts typically found in foods. Bilberry fruit extracts have been used safely in research studies at doses of up to 160 mg/day for up to 6 months and appear to be well tolerated. Bilberry leaves may be unsafe when consumed in high doses or for long periods of time. If you take any type of medicine, talk with your health care provider before using bilberry or other herbal products; some herbs and medicines interact in harmful ways. Little is known about whether it is safe to use bilberry in amounts greater than those found in foods during pregnancy or while breastfeeding.

Quoted in full from NCCIH so nothing is lost in summarising. Where they say “little is known”, that means the studies do not exist — not that the herb is known to be safe, and not that it is known to be harmful.

How much is actually known

Some research has been done in people on the effect of bilberry on various conditions, but many of the studies did not use rigorous methods and did not include enough study participants to allow definite conclusions to be reached.

What the research has found

Bilberry has not been clearly shown to be helpful for any health condition. Bilberries contain some substances that may be of interest for further research, including anthocyanins, anthocyanosides, tannins, and flavonoids. Studies of the effects of bilberry on night vision have had conflicting results. Much of the research was of poor quality. The most rigorous studies have not found bilberry to be effective in improving night vision in healthy people.

Before you take this

Dose and form change the answer completely. A culinary amount of a spice, a cup of tea, and a concentrated supplement extract are three different things, and most research is done on the last of them.

Supplements are also not regulated like medicines, so strength and purity vary between products. Bring the actual bottle to your midwife, doctor or pharmacist — that conversation is worth more than any page, including this one.