Spotlight: Vitamin A

What is it?

Vitamin A is a fat-soluble vitamin that is essential to growth (particularly cell division and differentiation), reproduction, bone development, and vision.  

Sources

Animal sources: liver, milk, cheese, egg substitute

Plant sources: carrots, kale, cantaloupe, tomato juice, peaches, red peppers, spinach, peas, mango, papaya

Deficiency 

Symptoms include poor night vision, higher risk of infections, and dry skin.  Deficiency is rarely seen in the United States but if so it is often paired with a zinc deficiency.  

Since Vitamin A is a fat-soluble vitamin, fat malabsorption in the body can lead to deficiency over time.  Conditions that see fat malabsorption include Celiac disease, Crohn's disease, and some pancreatic disorders.

Questions and Controversies

Smoking and Lung Cancer: Several studies have shown that Vitamin A supplementation has led to increased rates of lung cancer among individuals that already smoke.  

Osteoporosis: Several studies have shown that excessive intake of Vitamin A can block proper absorption of Calcium and Vitamin D into the bones and negatively affects bone mineral density. 

The Bottom Line

Don't look to supplements for Vitamin A, look to whole foods.  Vary your vegetables so that your plate is always very colorful, as these will contain different sources of Vitamin A and phytochemicals.