Are carrots good for you? What they really do for eyesight and blood sugar, and the few side effects worth knowing.
Carrots are one of the richest sources of beta-carotene, a plant pigment the body converts into vitamin A, and they also provide fiber (1, 8). For almost everyone, carrots are a safe and healthy food. But there are a few side effects of carrots worth knowing, especially if you eat or juice them in very large amounts, have a pollen allergy, or are feeding a young child.
A common myth is that eating too many carrots can easily cause vitamin A toxicity. As you will see below, the safety limit for vitamin A does not apply to the beta-carotene in carrots (1).
Key Takeaways
- The most common effect of eating very large amounts of carrots is carotenemia, a harmless yellow-orange skin color (1, 2).
- The vitamin A upper limit (3,000 mcg a day for adults) applies to preformed vitamin A from animal foods and supplements, not beta-carotene from carrots (1).
- Carrot allergy affects up to 25% of food-allergic people in some studies and is often linked to birch pollen allergy (4).
- Hard raw carrot pieces are a choking hazard for young children (7).
- High-dose beta-carotene supplements, not carrots, have been linked to lung cancer risk in smokers (1, 12).
Carrot Nutrition at a Glance
| Serving | Calories | Fiber | Vitamin A (from carotenoids) | Beta-carotene |
|---|---|---|---|---|
| Raw carrot, 1 medium (61 g) | 25 kcal | 1.7 g | 509 mcg RAE | 5.1 mg |
| Carrot juice, 1 cup (236 g) | 94 kcal | — | 2,256 mcg RAE | 22 mg |
Values calculated from USDA FoodData Central data for raw carrots and canned carrot juice (8, 9).
Do Carrots Improve Your Eyesight?
Partly, and the honest version is more interesting than the slogan. Carrots protect vision by preventing a deficiency. They do not sharpen eyesight that is already normal.
The deficiency part is real. Vitamin A deficiency causes night blindness and xerophthalmia, a condition that can damage the cornea and cost a child their sight. A systematic review of children in high-income countries collected 43 case reports and series covering 61 cases, and noted that these children are often misdiagnosed, which delays treatment 13. Carrots are one of the richest dietary sources of beta-carotene, which the body converts to vitamin A (1), so they genuinely do protect against this.
The part the slogan gets wrong is what happens once you have enough. A systematic review and meta-analysis of randomised trials of carotenoid-rich food and supplements found that visual acuity improved only in people who already had an eye disease. In healthy adults it did not 14. Eating more carrots than you need does not give you sharper vision, and no trial shows otherwise.
So the useful summary is this: if you are short of vitamin A, carrots matter a great deal. If you are not, they are a good vegetable that will not change your prescription.
Carrots, Blood Sugar and Diabetes
Carrots taste sweet, which makes people with diabetes wary of them. The measurement does not support that worry.
In a crossover study, 14 healthy adults ate portions of carrot, banana and plum each containing 25 g of available carbohydrate, with glucose as the reference. The glycemic index of carrot came out at 23 ± 9 — lower than banana (30) and plum (32), and all three produced significantly smaller blood glucose rises than glucose itself 15. That is a low glycemic index by any classification, and it puts carrots in the same group as the other vegetables we looked at in what people with diabetes can eat.
The reason is portion size as much as the vegetable. A medium carrot holds only about 25 calories and carries its sugars alongside 1.7 g of fibre (8), so the amount of carbohydrate arriving at once is small.
Carrot juice is the exception, and it is not a small one. A cup contains about 94 calories and the carotene of several carrots with the fibre removed (9). Juicing is also how most people reach the intakes that turn skin orange. Whole carrots and carrot juice do not behave the same way, and the difference matters most to the people asking this question.
1. Orange Skin (Carotenemia)
SaveCarotenemia happens when high levels of carotene in the blood give the skin a yellow-orange tint, most noticeable on the palms, soles and around the nose. It usually results from eating more than 30 mg of carotene a day for a prolonged period (2). A medium carrot contains about 5 mg of beta-carotene and a cup of carrot juice about 22 mg (8, 9), so you would need roughly six medium carrots or about a cup and a half of carrot juice every day for a long time.
Carotenemia is benign, but it can be mistaken for jaundice. It is seen most often in infants and young children, sometimes from large amounts of carrot-based baby foods, and it clears once carotene intake is reduced (2). Because jaundice can also cause yellow skin, see a doctor if the whites of your eyes turn yellow or you feel unwell.
2. Vitamin A Toxicity: Mostly a Myth for Carrots
Vitamin A toxicity is real, but it comes mainly from preformed vitamin A in supplements, liver and other animal foods. Chronic toxicity can cause dry skin, muscle and joint pain, fatigue and abnormal liver tests (1). The adult upper limit of 3,000 mcg a day applies only to preformed vitamin A. Beta-carotene from food is not known to cause birth defects or vitamin A toxicity; its most common effect with long-term excess is harmless skin discoloration (1).
There is one notable case report. A 48-year-old man who ate 6 to 7 pounds of carrots every week to help him diet developed abdominal discomfort, severe constipation, yellow-orange skin and raised liver enzymes. He was diagnosed with hypercarotenemia and possible vitamin A toxicity, and his liver tests returned to normal within a month of stopping (3). This involved extreme intake, far beyond normal eating.
Beta-carotene supplements are different. In large trials, taking 20 to 30 mg of beta-carotene supplements a day for several years increased the risk of lung cancer, mainly in smokers (1, 12). This applies to supplements, not to carrots as food. If you take supplements, see our article on supplement side effects for more on reading labels.
3. Carrot Allergy
Allergic reactions to carrot affect up to 25% of people with food allergies in some studies. In a study using double-blind food challenges, carrot allergy was confirmed in 20 of 26 people with a history of reactions, and all were sensitized to birch pollen-related carrot allergens (4). Most reactions are mild and affect the mouth, but severe reactions do occur:
- A person developed anaphylactic shock after eating ice cream that contained carrot as a hidden ingredient (5).
- An 11-year-old boy with pollen allergy had a systemic reaction within a minute of drinking raw carrot juice, with facial swelling, breathing difficulty and a rash (6).
If you have birch pollen allergy and notice itching or swelling after eating carrots, talk to an allergist. Seek emergency care for swelling of the throat, trouble breathing or dizziness. Other healthy foods can also cause allergic reactions; see our guide to avocado side effects.
4. Gas and Bloating
Carrots contain fiber. Adding a large amount of fiber to your diet quickly can cause gas, bloating and cramps, which usually improve as your gut adjusts; adding fiber gradually and drinking enough fluids helps (11). In the case report above, eating extreme amounts of carrots was linked to severe constipation (3).
5. Choking Risk for Young Children
SaveThe CDC lists pieces of hard raw vegetables, such as raw carrots, among foods that can be choking hazards for young children. Cooking foods to a soft texture and cutting or mashing them into appropriate sizes helps prevent choking, and children should always be supervised while eating (7).
How Many Carrots Are Safe to Eat?
There is no official daily limit for carrots. A medium carrot provides about 509 mcg RAE of vitamin A from carotenoids (8), and eating a few carrots a day as part of a varied diet is fine for most people. To avoid carotenemia, it helps not to eat more than about six medium carrots or a cup and a half of carrot juice every day for long periods (2, 8, 9). Carrots are also filling: in a study of young women, meals with whole carrots led to more fullness and lower food intake later in the day than meals with the same nutrients in non-fibrous form (10). For more on fruits and vegetables for weight control, see are apples good for weight loss.
Carrots are not the only produce whose colour tells you what is inside — the same logic separates honeydew from cantaloupe.
Frequently Asked Questions
Do carrots improve your eyesight?
Only if you are short of vitamin A. Deficiency causes night blindness and xerophthalmia, and carrots protect against that because the body converts their beta-carotene into vitamin A. But in a meta-analysis of randomised trials, carotenoid intake improved visual acuity only in people who already had an eye disease, not in healthy adults. Eating extra carrots will not sharpen vision that is already normal.
Can people with diabetes eat carrots?
Yes. Carrots taste sweet but measure low: in a crossover study their glycemic index came out at 23, below banana at 30 and plum at 32. A medium carrot has about 25 calories and 1.7 g of fibre, so little carbohydrate arrives at once. Carrot juice is the exception, with around 94 calories a cup and the fibre removed.
Can eating too many carrots be harmful?
For most people, eating lots of carrots is not dangerous. The most common effect of very high intake is carotenemia, a harmless yellow-orange skin color. In one case report, a man who ate 6 to 7 pounds of carrots a week developed constipation, high carotene levels and raised liver enzymes that returned to normal after he stopped.
How many carrots a day is too many?
There is no official limit for carrots, because the vitamin A upper limit applies only to preformed vitamin A from animal foods and supplements, not beta-carotene from plants. Carotenemia usually occurs with more than 30 mg of beta-carotene a day over a prolonged period, which is about six medium carrots or a cup and a half of carrot juice every day.
Can carrots turn your skin orange?
Yes. Eating large amounts of carrots or other carotene-rich foods for a long time can cause carotenemia, a harmless yellow-orange color most visible on the palms, soles and around the nose. It fades after you eat less carotene.
Can you be allergic to carrots?
Yes. Carrot allergy affects up to 25% of people with food allergies in some studies and is often linked to birch pollen allergy. Most reactions affect the mouth, but severe reactions including anaphylaxis have been reported.
Are raw carrots safe for babies and toddlers?
Pieces of hard raw carrot are a choking hazard for young children. Cook carrots until soft and mash or puree them, or cut them to a safe size and texture for your child’s age.
The Bottom Line
Carrots are safe and nutritious for most people. The main side effects of carrots are harmless orange skin with very high intake, allergic reactions in some people with pollen allergy, gas when fiber intake rises quickly, and a choking risk from hard raw pieces in young children. Carrots are very unlikely to cause vitamin A toxicity, because the vitamin A upper limit applies to preformed vitamin A, not beta-carotene. Enjoy carrots as part of a balanced diet, avoid high-dose beta-carotene supplements if you smoke, and serve carrots soft for young children.
This article is for informational purposes only and is not a substitute for professional medical advice. See a doctor if you notice yellow eyes, signs of an allergic reaction, or persistent digestive symptoms, and talk to a healthcare provider before taking vitamin A or beta-carotene supplements.
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