Vitamin A and Gut Health

 The gut hosts about 100 trillion bacteria. These bacteria regulate the activity of a protein called retinol dehydrogenase 7 (Rdh7) which further activates Vitamin A in the gastrointestinal tract, adjusting the body’s immune system response. 

Bacteria of the Clostridia family are known to diminish the expression of Rdh7. They also give a signal to the liver to store vitamin A. Research has unequivocally established that Rdh7 is the sole agent that is efficacious in triggering an appropriate response mechanism to bacteria. 

As protein Rdh7 transforms vitamin A to retinoic acid, the more active and usable form of Vitamin A, researchers feel a higher intake of Vitamin A can directly uplift the immune response.

Retinoids play a crucial role in every cell of the body. It strengthens the normal barrier function of the intestines. Malfunctioning of the intestinal mucosa affects the permeability of the intestinal epithelium, modifying the production of biochemical factors which in turn interact with gut microbes. Thus, research suggests that optimum intake of Vitamin A may impact gut health by bringing about changes in the intestinal mucosal barrier.

Vitamin A and Immune Function

Vitamin A is a fat-soluble vitamin that exists in three essential forms – retinol, retinal and retinoic acid. Retinol and retinal are the forms in which the body stores Vitamin A. While Retinal is crucial for vision, retinoic acid is the one that functions like a hormone and binds two distinct families of nuclear receptors (RAR and RXR) together. This is important for enhancing the function of all mucosal surfaces which boosts the body’s immune health.

Foods with Vitamin A

As per the recommended dietary allowance (RDA), the daily Vitamin A requirement is:

900 mcg for men

700 mcg for women

300-600 mcg for children

Here are the best foods that can help you meet this requirement:

1. Cod Liver Oil

Fish livers are a rich source of Vitamin A. 1 tbsp of cod liver oil provides around 4080 mcg of Vitamin A. Fish oils are also the richest source of Omega-3 fatty acids that combats inflammation and protects the heart.

2. Sweet Potatoes

One of the richest plant-based foods that have vitamin A is the sweet potato. The root vegetable contains Vitamin A in the form of beta-carotene, a carotenoid found in plants. The body breaks down beta-carotene to convert it into Vitamin A. A single sweet potato weighing around 100 gm provides around 1400 mcg of Vitamin A. 

3. Carrots

Carrots too are a rich source of beta carotenes. Carrots are a low-calorie, high-fibre food that helps promote gut health. A half-cup serving of fresh carrot contains around 460 mcg of Vitamin A. This makes up around 50% of the RDA value.

4. Black-Eyed Peas

Beans are a rich source of plant-based protein, dietary fibre and Vitamin A along with other vitamins and minerals. Each cup of boiled black-eyed peas provides around 66 mcg of Vitamin A. Black-eyed peas are also a rich source of iron and play a crucial role in promoting heart health. 

5. Spinach

Spinach is a green leafy vegetable that contains ample amounts of nutrients and vitamins. It is one of the healthiest foods that have Vitamin A. Each half-cup serving of cooked spinach provides 573 mcg of Vitamin A. It is also one of the healthiest sources of iron and magnesium.

6. Broccoli

Broccoli, a vegetable of the cruciferous family, is another healthy source of Vitamin A. A half-cup serving of broccoli provides 60 mcg of Vitamin A along with rich amounts of Vitamins K and C, together making up the immunity vitamins. Broccoli also contains high amounts of antioxidants and anti-inflammatory compounds.

7. Bell Pepper 

Bell pepper, especially red bell pepper, provides adequate Vitamin A to the body to promote gut health. A half-cup serving of red bell pepper contains 117 mcg of Vitamin A. Bell peppers are also a rich source of capsanthin, antioxidants that neutralise the effect of free radicals. It also contains good amounts of quercetin, an anti-inflammatory compound.

8. Mango

When it comes to fruits, mango contains high amounts of Vitamin A. Its high antioxidant count, natural sugars and dietary fibre contribute significantly to gut health. One medium-sized mango contains 180 mcg of Vitamin A.

9. Cantaloupe

A member of the melon family, the cantaloupe is a refreshing summer fruit. Besides containing high amounts of water, cantaloupe is also a great source of Vitamins A and C. Together they make up the best immunity vitamins. A half-cup serving of cantaloupe provides 135 mcg of Vitamin A.

10. Apricots

Apricots are a rich source of Vitamin A and beta-carotene. Every 100 gm serving of apricots contains around 96 mcg of Vitamin A. Its dried version, the dried apricot packs the same nutritional value. 10 dried apricots contain around 60 mcg of Vitamin A with a high amount of fibre and antioxidants.

11. Watermelon

Watermelon is one of the best foods to enjoy in hot summers. Around 92% of the watermelon by weight is water. But it contains some essential minerals and vitamins including Vitamin A and C. Every 100 gm serving of watermelon provides 28 mcg of Vitamin A.

12. Papaya

Papaya is a good source of Vitamin A. It also contains other immunity vitamins that support healthy immune system functioning. Lycopene is a natural pigment found in foods that are red or orange, protects the body from sun damage and protects the body from several cancers.

13. Tomato Juice

Tomatoes are a rich source of Vitamin C and lycopene, which work as antioxidants in the body. Its unique plant compounds and high amounts of Vitamin A make it extremely healthy for the gut. Around 180 ml serving of tomato juice contains 42 mcg of Vitamin A.

14. Guava

Guava packs the highest amounts of Vitamin C. Furthermore, the fruit also contains good amounts of Vitamin A. Every 100 gm serving of guava contains 31 mcg of Vitamin A which makes up for 3% of the daily recommended requirement of Vitamin A.

15. Passion Fruit

Passion fruit is a beneficial fruit with a healthy nutrition profile. It packs high amounts of vitamin A that improves eyes, skin, gut and immunity. Every 100 gm serving of passion fruit contains 64 mcg of Vitamin A.

Other Functions of Vitamin A

In addition to promoting gut health and boosting immune response, other function of Vitamin A includes:

Supports reproduction

Aids in healthy vision

Ensures proper functioning of important body organs like the heart, lungs, and kidneys

Promotes skin health

Improves growth and development, aids bone remodelling.

Conclusion

Vitamin A is activated by the gut bacteria in the gastrointestinal tract which in turn improves the immune function in the body. The role of vitamin A in gut health is profound. Foods that have vitamin A, therefore, go a long way in up keeping gut health and immune function. The best way to ensure maximum intake of Vitamin A is to include healthy amounts of foods with vitamin A.