Not only does vitamin D work with calcium to keep bones strong, but researchers now found that teenage girls with higher vitamin D levels may be able to jump higher and faster than their peers with lower levels, according to a new study published in the Journal of Clinical Endocrinology and Metabolism .

UK researchers collected vitamin D levels for 99 girls, ages 12 to 14. To test the girls' muscle function, the girls were instructed to jump as high as possible while researchers used a device designed to measure power and performance called jumping mechanography. After controlling for differences in the girls' body weight, the girls with the highest vitamin D levels had the highest jump speeds, jump height, power and force.

This potential muscle advantage adds to the growing list of evidence positioning vitamin D as a super nutrient. Well known for its role in keeping bones strong, vitamin D is now being hailed for so much more. Emerging science suggests vitamin D may also help protect against diabetes, hypertension, heart disease and certain cancers. It may also support a healthy immune system to ward off infections, and some preliminary evidence suggests it may affect longevity.

Yet despite a potential upside of boosting vitamin D levels, Americans of all ages still fall short of their vitamin D needs. Even in this study with demonstrated muscle benefits, overall, the girls' vitamin D levels were far less than ideal “ a finding consistent with numerous studies indicating a resurgence in vitamin D deficiencies in adolescence. In fact, current deficiency levels prompted the American Academy of Pediatrics to double the vitamin D recommendations for children and teens to 400 IU daily. The Academy estimates that up to half of adolescents have low vitamin D levels.

The recommended three glasses of lowfat or fat free milk a day delivers 75 percent of the vitamin D that's needed each day. Milk remains the leading source of vitamin D in the American diet “ it's one of the few food sources of the super nutrient. Plus, along with vitamin D, milk is a good source of calcium and high-quality protein “ two nutrients vital to help teens maintain bone density and lean muscle.

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AWASH has some tips to offer to reduce the salt in the diet and advise that in addition to checking the label and buying low salt foods when we shop, everyone can benefit from eating less salt by following these guidelines when eating out:-

When ordering pizza, choose vegetable or chicken toppings instead of pepperoni, bacon, or extra cheese.

When buying ready-to-eat packaged foods, choose low-salt options and compare products to find the one lowest in salt using the per 100g column on the Nutrition Information Panel.

Limit takeaways and fast foods such as burgers, fried chicken and pizza to an occasional treat and when eating out at a restaurant, ask for sauces and other condiments to be served on the side rather than on the meal and don't add salt to your food.

Keep healthy snacks such as dried fruit and unsalted nuts or fresh fruit handy and avoid ordering dishes that contain high salt ingredients including Asian sauces, cured meats and cheeses and ask about the salt content of meals and ask them not to salt the fries!

AWASH is a growing network of individuals and organisations concerned with salt and its effects on health which each year co-ordinates World Salt Awareness Week to highlight the health problems caused by eating too much salt and raise awareness of action needed to be taken.

The theme for this year's World Salt Awareness Week (2nd - 8th February) is Salt and Eating Out and the event Salt and the City will bring together representatives of the food and catering industries with health professionals, food critics, academics and media personnel to raise awareness of high salt levels in foods eaten outside of the home and discuss actions that can be taken to improve food choices.

The book, Health & the City by Caitlin Reid provides simple and practical tips for incorporating healthy practices into busy city lifestyles and more information can be gleaned about World Salt Awareness Week by visiting www.awash.au.