Red, blue, green, yellow... They certainly are varied. Swallow them and you are promised everything from glowing skin to a heart beating like a finely-tuned engine. What’s more, you feel good about yourself — you’ve taken your daily dose of vitamins.

But the party was pooped this week when The Cochrane Collaboration, an independent watchdog that monitors the health care industry, revealed that we may be overdosing on vitamins and, as a result, “shortening our lives”.

These days one doesn’t know which “study” to believe. Cochrane has an unblemished reputation for independent clinical studies, and it’s true the pharmaceutical industry has been in hot water before over vitamins.

Supplements are big money, and in 1999 multinationals including Roche, Rhone-Poulenc, BASF and Takeda were fined by the US government for forming a “price-fixing cartel”.

The Cochrane study specifically targets three vitamins — A, C and E. The fact that an overdose of fat-soluble vitamin A, retinol, is harmful has been known for some time.

It causes hypervitaminosis, making the bones brittle. Vitamin C, ascorbic acid, is water-soluble and has only temporary overdose effects.

But vitamin E, tocopherol, every cardiologist’s favourite, is a different ball game. Again a fat-soluble vitamin, it tends to be retained by the body. The Cochrane study found that the same antioxidants that help fight cancer in small doses may aid it in bigger quantities.

Nutritionist Ishi Khosla says that “It is an increasing trend” to pop supplement pills, thanks to aggressive marketing by pharma companies.

“The trend was confined to the upper crust of society but is slowly but surely making its way across all sections... The companies are reaching out to more potential consumers and their products get noticed.”

Khosla says that, in theory, a well-balanced diet will meet all requirements of vitamins and minerals. But food habits today make it hard to avoid supplements. She advises caution, though, especially for vitamins that are fat-soluble.

“Vitamin E especially must be got only from natural sources or, even for therapy, consumed only in tiny quantities,” she cautions.

Finally, there is one trend unique to India. According to Khosla, we lack vitamin D (calciferol). Even though we enjoy sunny climes, she says, we hardly spend any time outdoors, thus impairing the production of the vitamin, deficiency of which can aggravate osteoporosis. So don’t wait: rush out and soak in the summer sun!