Vitamin A deficiency is uncommon in the general US population, estimated at around 0.3 percent, but the picture changes sharply in people with gut, liver or pancreatic problems.
Clinicians writing in the NIH StatPearls reference note that pancreatic, liver and intestinal disease drive most cases in wealthy countries, and that roughly 16 percent of children with inflammatory bowel disease in the US already have vitamin A deficiency at diagnosis.
The reason so many at-risk groups involve the gut is basic chemistry. Vitamin A is fat-soluble, so the body needs dietary fat and bile to absorb it. Cleveland Clinic lists celiac disease, cystic fibrosis, chronic diarrhea, bariatric surgery and alcohol use disorder as common risk factors, alongside liver disorders that block storage.
What early deficiency looks like
The signs below are drawn from the NIH StatPearls entry and Cleveland Clinic. They tend to appear gradually, and the eyes are usually first to complain.
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1. Trouble seeing in dim light. Night blindness, known clinically as nyctalopia, is the classic first symptom. Vision is fine in daylight but struggles in a dark parking lot or a dim restaurant.
2. Dry, gritty eyes. As deficiency deepens, the whites of the eyes and the corneas stop producing enough tears, a condition called xerophthalmia. Left untreated, it can progress to corneal ulcers and permanent vision loss.
3. Foamy white spots on the whites of the eyes. Called Bitot spots, these triangular or oval patches on the conjunctiva are a hallmark of the deficiency and easy to see in a mirror.
4. Rough, scaly or itchy skin. Chronic dryness and scaling can develop across large areas of the body as the skin's mucosal barrier weakens.
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5. Bumpy skin on the shoulders, buttocks and outer arms. Doctors call this phrynoderma, a form of follicular hyperkeratosis that leaves small horny plugs on extensor surfaces. It is a specific dermatologic sign of the deficiency.
6. Frequent respiratory and throat infections. Vitamin A supports the immune system and the mucous membranes lining the airways. When it runs low, chest infections and sore throats become more common.
7. Trouble conceiving. Cleveland Clinic notes that vitamin A deficiency can lead to fertility problems and trouble conceiving.
8. Slowed growth in children. In kids, low vitamin A shows up as delayed physical development, not just eye or skin signs.
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Who is most at risk in the US
Serious deficiency is unusual in healthy adults eating a mixed diet, but the numbers climb steeply in some groups.
StatPearls reports roughly 70 percent prevalence in transplant-eligible patients with liver cirrhosis, about 35 percent in people with chronic pancreatic insufficiency, and up to 70 percent three years after biliopancreatic diversion, a form of weight-loss surgery. People on very-low-fat diets or with untreated Crohn's disease and celiac disease are also flagged as vulnerable because they cannot absorb the vitamin properly.
How to fix it through food
The recommended dietary allowance is 900 micrograms of retinol activity equivalents per day for adult men and 700 for adult women, according to Harvard's Nutrition Source, and this is easily met from ordinary foods.
Beef liver is by far the most concentrated source and a small serving can push intake well above a full day's requirement on its own. Cleveland Clinic also lists eggs, dairy, fish, leafy greens, broccoli, carrots, pumpkin and sweet potatoes as reliable everyday sources.
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There is a catch. Because vitamin A is fat-soluble, tossing a splash of olive oil or a pat of butter onto a plate of carrots or spinach helps the body actually absorb what is on the plate.
Supplements are not a shortcut
Reaching for a high-dose supplement can backfire. The tolerable upper intake for adults is 3,000 micrograms of preformed vitamin A per day from Harvard's summary of federal guidance, and going beyond it over time is linked to blurred vision, bone pain, dry skin and nausea.
StatPearls flags that in the US, vitamin A toxicity is actually more common than deficiency. A separate concern is that nearly 2,000 US children were hospitalized in three years for taking too many vitamins, a reminder that these products are not risk-free.
Anyone with persistent night vision problems, unexplained dry eyes or skin changes, or a diagnosed condition affecting fat absorption should discuss testing and any supplement use with a doctor before self-treating.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.