Facts

Whole grains:

contain as much as four times the amount of dietary fiber than found in refined grains. Fiber has been shown to reduce the occurrence of some forms of cancer, digestive system diseases, cardiovascular diseases, diabetes, gum disease, and obesity. Some of these effects occur because the carbohydrates from whole grains are digested much more slowly than refined grains, causing them to enter the bloodstream at a slower rate. Whole grain foods also have a lower calorie content

Sweet potatoes:

contain a lot of dietary fiber, complex carbohydrates, beta carotene (vitamin A), vitamin C, and vitamin B6. Studies have been done which show that sweet potatoes are beneficial to diabetics because they can help stabilize blood sugar level and lower insulin resistance.

Nuts:

studies have shown that people who eat nuts on a daily basis are less likely to get coronary heart disease. It has also been found that the consumption of nuts can and can also help with insulin resistance.

Fruits:

high in fiber, water, and vitamin C. They also contain phytochemicals, which can possibly help in long-term cellular health and disease prevention. Eat fruits on a regular basis reduces the risks of cancer, cardiovascular disease, stroke, Alzheimer disease, cataracts, and some of the problems that come with aging.

Vegetables:

most contain small portions of protein and fat along with high portions of vitamins, provitamins, dietary minerals, fiber and carbohydrates. Many vegetables also contain phytochemicals.

Soy:

considered to be a source of complete protein, which contains large amounts of all the essential amino acids that must be provided to the human body because the body is not able to synthesize them on its own. For this reason, soy is a good source of protein. It has also be found that soy may reduce the risk of colon cancer.

Green tea:

contains many antioxidants. Studies have shown that green tea can help increase life expectancy, decrease the risk of cardiovascular disease, breast, ovarian, and prostate cancer, obesity, and cognitive illnesses.

All facts mentioned in this section have come from Wikipedia as well as my own knowledge.