UNUSUALLY long, cold winters. Beyond-hot, scalding summers. Deaths due to heat wave. Pneumonia casualties.

If you think think global warming and climate change are far-away dangers, think again.

The World Health Organisation has declared today, April 7 as the World Health Day . In 2008, it's marked for fighting the climate change, the healthy way.

We talked to some experts for great ways to build immunity and boost metabolism - a perfect way to cope with the vagaries of the weather. 

Never feel under the weather, make sure you enjoy it!

The Immunity boosters

"The overall upkeep of your health will depend upon how healthy you are and how much you eat. Basically, for a healthy adult, her diet should contain foods from all food groups. However, there are certain foods that contain potential nutrients and minerals to boost your body's capacity to fight diseases," explains nutritionist Sushila Sharangdhar.

Sushila enlists these immune boosting foods help you increase the white blood cells in your body and thus help fight diseases.

Vitamin C: Foods rich in vitamin c help you counter attack viruses and repair your body's immune response to infections.

Since your body cannot store or form vitamin c, it has to rely on your dietary intake. Some of the best sources of this vitamin are tomato, potato, kiwi, orange and bell peppers.

Zinc: It helps white blood cells and other antibodies reproduce more quickly. Zinc deficiency, even if moderate, can suppress immune system function. Severe deficiency can shut the immune system down completely.

Some of its food sources are: seafood, eggs, red meat, yogurt, milk, beans etc.

However, remember an excess of it can also be dangerous. An excess of it can suppress your body's absorption level of copper and iron, thus making you anaemic.