Vitamin A Deficiency: Risks and Safe Intake in Pregnancy

Vitamin A is a fat-soluble vitamin essential for vision, immune function, cell differentiation, and embryonic development. It exists in two forms in the diet: preformed vitamin A (retinol), found in animal products, and provitamin A carotenoids (such as beta-carotene), found in colourful fruits and vegetables. During pregnancy, vitamin A plays a vital role in the development of the baby's eyes, skin, lungs, and immune system.

Vitamin A deficiency is a public health concern in many developing countries, including certain regions of India. The deficiency can impair immune function, increase susceptibility to infections, and in severe cases cause night blindness. However, vitamin A is unique among nutrients because both deficiency and excess can be harmful during pregnancy, requiring careful balance.

The recommended daily intake of vitamin A during pregnancy is approximately 800 micrograms of retinol activity equivalents (RAE). Understanding the difference between safe food-based sources and potentially harmful supplemental doses is important for every expecting mother.

The primary cause of vitamin A deficiency is a diet lacking in fruits, vegetables, dairy products, and other animal-based foods that provide preformed vitamin A or beta-carotene. In some communities in India, diets may be monotonous and lack the diversity of colourful vegetables and fruits needed to supply adequate carotenoids. Seasonal availability of certain produce can also affect intake.

Fat malabsorption conditions impair the absorption of vitamin A, as it is a fat-soluble vitamin that requires dietary fat for proper uptake. Conditions such as celiac disease, chronic pancreatitis, and bile duct obstruction can reduce vitamin A absorption. Women with liver disease may also have difficulty storing and metabolising this vitamin.

Infections, particularly gastrointestinal infections and measles, can deplete vitamin A stores rapidly. Chronic diarrhoeal diseases, common in certain populations, increase vitamin A losses. Women who enter pregnancy with already low vitamin A status due to poverty, limited food access, or chronic illness are at the highest risk of clinically significant deficiency.

The earliest clinical sign of vitamin A deficiency is impaired dark adaptation, also known as night blindness, where you have difficulty seeing in dim light or adjusting when moving from a bright to a dark environment. Dry eyes, characterised by reduced tear production and a gritty feeling, can also indicate low vitamin A levels. In severe cases, a condition called Bitot's spots (foamy white patches on the conjunctiva) may appear.

Other symptoms include dry, rough, or scaly skin, increased susceptibility to infections (particularly respiratory and gastrointestinal infections), and slow wound healing. Some women may experience a diminished sense of taste. Because mild deficiency may be asymptomatic, women with risk factors should discuss vitamin A testing with their healthcare provider.

For the mother, vitamin A deficiency increases vulnerability to infections and can worsen pregnancy-related anaemia. Night blindness during pregnancy is a recognised indicator of vitamin A deficiency in public health assessments. Severe deficiency can impair immune function and increase the risk of maternal morbidity and mortality, particularly in resource-limited settings.

For the baby, vitamin A is essential for lung maturation, eye development, and the formation of the immune system. Deficiency during critical periods of organogenesis can contribute to developmental abnormalities. However, it is equally important to note that excessive vitamin A intake, particularly from preformed retinol in supplements, is teratogenic and can cause birth defects affecting the heart, brain, and facial structures.

This dual risk makes vitamin A a nutrient that requires careful attention. The safest approach is to meet vitamin A needs primarily through food, especially beta-carotene-rich fruits and vegetables, which the body converts to vitamin A as needed without the risk of toxicity associated with preformed retinol supplements.

Beta-carotene-rich foods are the safest way to meet vitamin A needs during pregnancy. Excellent sources include carrots, sweet potatoes, pumpkin, mango, papaya, and dark green leafy vegetables such as spinach, moringa leaves, and amaranth. Orange and yellow vegetables commonly available in Visakhapatnam markets are affordable and versatile ingredients that can be incorporated into everyday meals.

Animal-based sources of preformed vitamin A include eggs, milk, curd, butter, and fish liver oils. These should be consumed in moderate amounts during pregnancy. Liver, while extremely rich in vitamin A, should be avoided or consumed very sparingly during pregnancy because its retinol content can reach levels that pose a risk of toxicity.

Avoid high-dose vitamin A supplements unless prescribed by your doctor for confirmed deficiency. Most prenatal vitamins contain safe amounts of vitamin A, often in the form of beta-carotene rather than retinol. Read supplement labels carefully and do not take multiple supplements that contain vitamin A. If in doubt, consult your healthcare provider about the appropriate form and dosage for your situation.

Seek medical advice if you experience night blindness, persistent dry eyes, or frequent infections during pregnancy. Your doctor can assess your vitamin A status through a clinical examination and, if needed, a serum retinol test. In Visakhapatnam, ophthalmologists and obstetricians can work together to evaluate and manage eye-related symptoms during pregnancy.

Discuss your vitamin A intake with your healthcare provider, especially if you are taking any supplements, have a history of liver disease, or follow a very restrictive diet. Given the narrow range between deficiency and excess, professional guidance is especially important for this nutrient. Your doctor can ensure that your prenatal supplementation plan provides adequate vitamin A without exceeding safe limits for pregnancy.