Lemons are high in vitamin C, fiber, and various beneficial plant compounds.
These nutrients are responsible for several health benefits.
In fact, lemons may support heart health, weight control, and digestive health.
Here are 6 evidence-based health benefits of lemons.
1. Support Heart Health
Lemons are a good source of vitamin C
One lemon provides about 31 mg of vitamin C, which is 51% of the reference daily intake (RDI).
Research shows that eating fruits and vegetables rich in vitamin C reduces your risk of heart disease and stroke (1Trusted Source, 2Trusted Source, 3Trusted Source).
However, it’s not only the vitamin C that is thought to be good for your heart. The fiber and plant compounds in lemons could also significantly lower some risk factors for heart disease (4Trusted Source, 5Trusted Source).
For instance,one study revealed that eating 24 grams of citrus fiber extract daily for a month reduced total blood cholesterol levels (6).
Plant compounds found in lemons — namely hesperidin and diosmin — have also been found to lower cholesterol (7Trusted Source, 8Trusted Source, 9).
2. Help Control Weight
Lemons are often promoted as a weight loss food, and there are a few theories as to why this is.
One common theory is that the soluble pectin fiber in them expands in your stomach, helping you feel full for longer.
That said, not many people eat lemons whole. And because lemon juice contains no pectin, lemon juice drinks will not promote fullness in the same way.
Another theory suggests that drinking hot water with lemon will help you lose weight.
However, drinking water is known to temporarily increase the number of calories you burn, so it may be the water itself that is helping with weight loss — not the lemon (10Trusted Source, 11Trusted Source).
Other theories suggest that the plant compounds in lemons may aid weight loss.
Research shows that plant compounds in lemon extracts may help prevent or reduce weight gain in a number of ways (12Trusted Source, 13Trusted Source).
In one study, mice on a fattening diet were given lemon polyphenols extracted from the peel. They gained less weight and body fat than other mice (14Trusted Source).
However, no studies confirm the weight loss effects of lemon compounds in humans.
3. Prevent Kidney Stones
Kidney stones are small lumps that form when waste products crystallize and build up in your kidneys.
They are quite common, and people who get them often get them repeatedly.
Citric acid may help prevent kidney stones by increasing urine volume and increasing urine pH, creating a less favorable environment for kidney stone formation (15Trusted Source, 16Trusted Source).
Just a 1/2-cup (4 ounces or 125 ml) of lemon juice per day may provide enough citric acid to help prevent stone formation in people who have already had them (17Trusted Source, 18Trusted Source).
Some studies also found that lemonade effectively prevented kidney stones, but the results have been mixed. Other studies have shown no effect (19Trusted Source, 20Trusted Source, 21Trusted Source, 22Trusted Source).
Therefore, more well-conducted studies need to examine whether lemon juice affects kidney stone formation (23Trusted Source, 24Trusted Source, 25Trusted Source).
4. Protect Against Anemia
Iron deficiency anemia is quite common. It occurs when you don’t get enough iron from the foods you eat.
Lemons contain some iron, but they primarily prevent anemia by improving your absorption of iron from plant foods (26Trusted Source, 27Trusted Source).
Your gut absorbs iron from meat, chicken, and fish (known as heme iron) very easily, while iron from plant sources (non-heme iron) not as easily. However, this absorption can be improved by consuming vitamin C and citric acid.
Because lemons contain both vitamin C and citric acid, they may protect against anemia by ensuring that you absorb as much iron as possible from your diet.
5. Reduce Cancer Risk
A healthy diet rich in fruits and vegetables may help prevent some cancers (28Trusted Source).
Some observational studies have found that people who eat the most citrus fruit have a lower risk of cancer, while other studies have found no effects (29Trusted Source, 30Trusted Source, 31Trusted Source).
In test-tube studies, many compounds from lemons have killed cancer cells. However, they may not have the same effect on the human body (32Trusted Source, 33Trusted Source, 34Trusted Source).
Some researchers think that plant compounds found in lemons — such as limonene and naringenin — could have anticancer effects, but this hypothesis needs further investigation (5Trusted Source, 35Trusted Source, 36Trusted Source, 37Trusted Source).
Animal studies indicate that D-limonene, a compound found in lemon oil, does have anticancer properties (38Trusted Source, 39Trusted Source).
Another study used pulp from mandarins that contained the plant compounds beta-cryptoxanthin and hesperidin, which are also found in lemons.
The study discovered that these compounds prevented malignant tumors from developing in the tongues, lungs, and colons of rodents (40Trusted Source).
However, it should be noted that the research team used a very high dose of the chemicals — far more than you would get by eating lemons or oranges.
While some plant compounds from lemons and other citrus fruits may have anticancer potential, no quality evidence suggests that lemons can fight cancer in humans.
6. Improve Digestive Health
Lemons are made up of about 10% carbs, mostly in the form of soluble fiber and simple sugars.
The main fiber in lemons is pectin, a form of soluble fiber linked to multiple health benefits.
Soluble fiber can improve gut health and slow the digestion of sugars and starches. These effects may result in reduced blood sugar levels (41Trusted Source, 42Trusted Source, 43Trusted Source, 44Trusted Source).
However, to get the benefits of fiber from lemons, you need to eat the pulp.
People who drink lemon juice, without the fiber found in the pulp, will miss out on the benefits of the fiber.