A deficiency of virtually any nutrient can significantly impair immunity. Worldwide, nutrient deficiency is by far the most common cause of poor immune function. This fact is by no means limited to people whose diets are restricted by poverty. In the United States, many people are overfed but undernourished. They choose foods that have a lot of calories but little real nutritional value. Here are some tips that you can greatly benefit from if you follow these guidelines to the letter.

1. Take a high potency vitamin and mineral supplement

Doing so will increase your intake of key nutrients for immune function, as explained below. Not long ago, a study of adults found that those who took a multivitamin and mineral supplement had a 50 percent decrease in the number of sick days due to infection compared to the group that took a placebo (the pill fictitious). Those who took the supplement also showed improvement in eight of twelve objective measures of immune function. Very good results for so little effort!

2. Reduce the intake of saturated fat and cholesterol

A diet high in saturated fat suppresses immunity. Many people who initially have high cholesterol and triglyceride levels also report more frequent colds and flus. When cholesterol and triglyceride levels return to normal, proper immune function is restored.

3. cut the sweet stuff

Sugar makes your white blood cells slow. Studies show that eating 100g of sugar reduces the effectiveness of a type of white blood cell known as a neutrophil, which engulfs and destroys bacteria, by up to 40 percent within two hours of ingesting it. Since neutrophils make up about 60 to 70 percent of your white blood cells, interfering with them can seriously impair your immune function.

4. Eat sufficient but not excessive amounts of protein

Adequate protein intake is critical for the production of white blood cells, antibodies, and chemical messengers such as interferon. You also need protein to make antioxidant enzymes like glutathione, which is found in abundance in white blood cells. Elevated glutathione levels are associated with improved immune function. People with low immune function may benefit from eating more protein from fish, lean poultry, and lean cuts of meat. There are many vegetarians who suffer from low immunity solely as a result of not consuming enough protein. I would recommend soy protein isolate if you eat absolutely no animal products, or whey protein if you eat dairy. An additional 40-50g per day for a month will boost protein stores to normal. After the month is up, I would still recommend 20g of either option a day.

5. eat plant food

Eat a diet that is rich in a variety of vegetables, especially green leafy ones, fresh fruits, whole grains, beans, nuts, and seeds. These plant foods are rich in essential nutrients and chemicals that boost the immune system.