Protein is an essential nutrient needed to maintain and repair the cells in your body -- it also plays a key role in healthy weight management, according to a review published in 2008 in the “American Journal of Clinical Nutrition.

While no major studies link high protein intake to kidney disease in healthy people, excess protein does force your kidneys to work harder and can cause problems for people with existing medical conditions. Kidney disease aside, the healthiest diet is a varied one that contains a balance of nutrients.

Keeping your metabolism high is one of the best ways to lose weight. If you have a high metabolism, you'll be able to break down foods quickly and keep your internal energy stores high. Eating small portions frequently is a great way to keep your metabolism high, but not everyone has the time to eat every few hours.

In an ideal world, you can kick your feet up and relax for the nine months of your pregnancy to give your changing body a break. In reality, life goes on, even as you progress. During the final weeks of your pregnancy, however, it is important to take it easy.

When small organic molecules bind together, they form larger molecules called biological macromolecules. Biological macromolecules fall into four categories: carbohydrates, proteins, lipids and nucleic acids. Your body uses carbohydrates, lipids and proteins for energy.

Inappropriate amounts of calcium during pregnancy may be bad for both you and the baby, but excess calcium can also lead to dire consequences.

The mineral manganese is essential for normal brain and nerve function and it plays an important role in helping the body form bones, tissue and sex hormones. However, in large doses, this mineral is also potentially toxic.

Whey is a byproduct formed during the making of cheese. Once thought of as a waste product, whey is today recognized as one of the highest quality sources of protein on the planet. In fact, it features the highest biological value of any protein, meaning it is digested and absorbed more efficiently than other proteins.

The dietary sodium in table salt is essential to electrical nerve and muscle body functions, but over-consuming sodium is a health risk. When your blood sodium is too high from eating salty foods, your kidneys must work to restore a balance of electrolytes and fluids.

Niacin, or vitamin B-3, is water-soluble, meaning your body doesn't store it and can flush out excess amounts in your urine. For this reason, you're unlikely to get too much niacin from food alone.

Refined carbohydrates are made from carbohydrates that are extensively processed and transformed. Foods made from white flour and sugar are refined. Unfortunately, many Americans eat refined carbs on a daily basis.

Protein is one of the nutrients you need to stay healthy, and it helps provide for the needs of your developing fetus during pregnancy. The 2004 "Journal of Nutrition"