Do vitamins cause weight gain?

By taking multivitamins, there’s an increased chance that your body will have all the nutrients it needs to function properly.

This may impact upon your weight because of the effect on the metabolism, which is assisted by a wide variety of nutrients. Importantly, your metabolism regulates the rate at which the body burns off kilojoules, and a well functioning metabolism is important for weight control.

Your intake of nutrients may also impact upon appetite and therefore food intake. For example, low levels of vitamin B6 is associated with a decrease in brain serotonin levels which could result in an increased appetite.

On the other hand, some people may blame multivitamins for weight gain or a lack of weight loss because they ignore the bigger picture of their overall lifestyle. This is especially true of people who take multivitamins because their diet is otherwise lacking.

If you are taking multivitamins because you are not eating healthily, you are inactive, or because you are on a restrictive diet, it could be these associated behaviours responsible for weight gain, not the multivitamin.

Research

Recent research published in the British Journal of Nutrition suggested that multivitamins may actually assist weight loss in men.

Men who regularly consumed vitamin and dietary supplements had a lower body weight, fat mass, and body mass index compared to men who did not take multivitamins.

The same study found there was a trend towards similar results in the opposite sex, and women also experienced reduced hunger levels. A multivitamin and mineral supplement was found to significantly decrease appetite ratings in women after weight loss, compared with a placebo group which had also lost weight.

According to the researchers, vitamins and minerals are involved in the synthesis of hunger hormones such as insulin, leptin and cortisol that control food intake.

Lifestyle implications

The implications from this study are relevant for both men and women who are managing their weight. Consider the following points.

• If your goal is to lose body fat, or maintain a healthy level of body fat, taking a multivitamin and mineral supplement regularly may help you get results.

• Eat a highly nutritious diet rich in vegetables, legumes, whole grains, lean protein sources and fruits. Don’t rely on a multivitamin to supply all the nutrients your body needs, or use it as an excuse to eat unhealthy foods.

• Multivitamins are not a substitute for regular physical activity. Exercise is a vital component of a weight control program.

• If you have already lost weight, a multivitamin and mineral supplement may help reduce your appetite, which may help prevent weight re-gain.

BIO:Andrew Cate is a university qualified exercise physiologist, food coach and author of five books on weight control. Andrew's latest book "Walk Off Weight" includes an eight week food and exercise plan, with tasty recipes and meal plan ideas. For more information visit www.andrewcate.com