Where it comes from: Vitamin A is a fat-soluble vitamin that is found in many fruits, vegetables, eggs, whole milk, butter, fortified margarine, meat and oily saltwater fish. It’s also made in supplemental pill form. What it’ll do for you: Vitamin A is required for the proper development and functioning of our eyes—not getting enough Vitamin A could result in night blindness or dry eyes. It also plays a key role in keeping skin healthy and the immune system strong. Here, a look at other important benefits:
- Prevents and helps treat cancer Some experts have looked into Vitamin A—in combination with beta-carotene—for links in preventing certain cancers (including cervical, esophageal, pancreatic, colorectal and more). So far, there has been insufficient evidence. However, limited research suggests that taking Vitamin A by mouth might improve survival rates and reduce the development of new tumors in people with lung cancer.
- Boosts the immune systems Vitamin A helps the linings of the eyes, respiratory, urinary and intestinal tracts stay healthy. When those lining break down, it becomes easier for bacteria to enter the body and cause infection. It also makes white blood cells that destroy harmful bacteria and viruses. Some research proves that Vitamin A may also help certain white blood cells fight infections more effectively.
Suggested intake: “Food is an ideal source of Vitamin A,” explains Sarah Currie, RD and personal trainer for New York City-based Physical Equilibrium LLC. Good sources include liver, fish liver oils, yellow and green leafy vegetables (squash, carrots, peas, etc.), yellow fruits (peaches, mangos, etc.), eggs, whole milk dairy products and vegetable oils (especially deep red palm oil). The recommended dietary allowance of Vitamin A for adult males is 900 micrograms per day. “A balanced diet can keep a man safe from toxicity and deficiency—and supplementation shouldn’t be necessary,” says Currie. Supplements are available, but because Vitamin A can build up to toxic levels in the body, some experts recommend getting it through beta-carotene supplements, which prompt the body to produce Vitamin A on its own. Associated risks/scrutiny: “Consuming excessive levels of Vitamin A—usually from supplementation—can cause liver abnormalities and reduced bone mineral density,” warns Currie. Additionally, long-term use of large amounts of Vitamin A might cause fatigue, irritability, mental changes, anorexia, stomach discomfort, nausea, vomiting, mild fever, excessive sweating and other unpleasant side effects.