Chase those monthly blues away with a diet rich in calcium and vitamin D

U.S. researchers say that a diet rich in calcium and vitamin D might very well help banish pre-menstrual syndrome (PMS).

A large number of women experience mild emotional or physical symptoms before their period, but as many as 20% have more severe symptoms which can be quite debilitating.

There are many theories about why PMS occurs, but some experts believe it is triggered by fluctuations of the sex hormones during the menstrual cycle which causes a drop in progesterone or an increase in oestrogen, during the latter half of the menstrual cycle.

In their study, researchers at Massachusetts University compared the diets of 1,000 women with PMS and 2,000 women without PMS.

They found that those without PMS appeared to eat more vitamin D and calcium-rich foods like milk, cheese, broccoli and cereals, and that blood calcium and vitamin D levels are lower in women with PMS.

Earlier studies have reported that calcium supplements appear to ease PMS, but now this new research suggests both calcium and vitamin D might reduce the risk of PMS and may influence levels of the female hormone oestrogen.

The researchers found after adjusting for factors like the woman's age, how many children she had and whether she smoked, the women with the highest intake of vitamin D and calcium were significantly less likely to have PMS.

Scientist Elizabeth Bertine-Johnson says they observed a significantly lower risk of developing PMS in women with high intakes of vitamin D and calcium from food sources, equivalent to about four servings per day of skim or low-fat milk, fortified orange juice or low-fat diary foods such as yoghurt.

The amounts they consumed were slightly above the current recommended daily amounts in the UK, which are 800 milligrams of calcium and 5 micrograms of vitamin D.

Vitamin D is known to help the body absorb calcium and both are essential for healthy bones.

Professor Shaughn O'Brien, an expert on PMS from Keele University, said the findings provided a basis for a clinical trial to see whether this was a real effect.

He said following a healthy, balanced diet was sensible for anyone and that there are drug treatments which have been shown to be helpful for women with severe PMS, such as antidepressants, which ease the physical as well as the psychological symptoms.

The study authors agree that clinical trials are warranted but meanwhile given that calcium and vitamin D may also reduce the risk of osteoporosis and some cancers, they say clinicians should consider recommending these nutrients even for young women.

The study is published in the Archives of Internal Medicine.