Lemons (Citrus limon) are a citrus fruit known for their sour, bitter flavor and bright yellow color. They’re also packed with vitamin C and antioxidants that support various aspects of health. For example, lemon water has gained popularity for helping to reduce the risk of kidney stones, promoting vitamin C intake, and supporting healthy digestion.
Kidney stones, also known as renal calculi or nephrolithiasis, are hard deposits made of minerals that build up in your urinary tract and form in your kidneys. They affect about 10% of people. You can prevent kidney stones by increasing your levels of a weak acid called urine citrate or by making your urine more alkaline.
Lemons contain a form of citrate called citric acid, which helps increase urine citrate levels. Citric acid binds with urinary calcium to help prevent oversaturated urine. It also binds to hard clumps of minerals called calcium oxalate crystals to prevent them from growing and becoming painful kidney stones.
Tip: According to the National Kidney Foundation, consuming four ounces of lemon juice concentrate mixed with water daily may help prevent kidney stones. However, if your urine pH levels are too acidic, an alkali citrate such as potassium citrate may be better. Speak with your doctor about your risk for kidney stones and the best prevention options for you.
Lemons are rich in vitamin C and other antioxidants that support heart health.
Consuming adequate vitamin C protects your cells from free radicals—highly unstable particles that can cause damage to cells if they aren’t neutralized. This can help prevent atherosclerosis (plaque buildup in the arteries), a condition that increases your risk of heart attack and stroke.
Lemons contain phenolic compounds, a type of antioxidant that supports healthy blood pressure, endothelial function, and low-density lipoprotein (LDL) cholesterol levels. Endothelial function refers to how smoothly blood runs throughout your body. Hypertension (high blood pressure), high LDL cholesterol levels, and reduced endothelial function increase your risk of heart disease.
Eating lemons also increases your total fruit and vegetable intake. A large 2017 study found that higher fruit and vegetable intake was associated with reduced risk of cardiovascular disease, cancer, and all-cause mortality (risk of death due to any cause).
One lemon contains over 30% of the daily value (DV) for vitamin C, which is important for iron absorption.
Specifically, vitamin C helps you absorb nonheme iron, which is found in plants and iron-fortified foods like bread and cereals.
Pairing vitamin C with food sources of iron helps you absorb iron more effectively. This can be especially beneficial if you’re vegan or vegetarian and consume primarily nonheme iron. It can prevent iron deficiency anemia, a condition caused when your body does not have enough iron to produce hemoglobin—the protein in red blood cells that carries oxygen throughout your body.
Numerous studies have shown that citrus fruits are rich in antioxidants.
Antioxidants in lemons help prevent cell damage associated with health conditions like cardiovascular disease, chronic kidney disease, cancer, and chronic obstructive pulmonary disease (COPD). COPD is a group of chronic, progressive lung diseases that limit airflow to your lungs and cause difficulty breathing.
Tip: Eat the peel! Recent research shows that citrus peels contain even higher amounts of health-promoting antioxidants than the juice and flesh.
One lemon without the peel has the following nutrition profile:
- Calories: 17
- Fat: 0.2 grams (g)
- Sodium: 1 milligram (mg)
- Carbohydrates: 5 g
- Fiber: 1.6 g, or 6% of the DV
- Added sugars: 0 g
- Protein: 0.6 g
- Vitamin C: 31 mg, or 34% of the DV
Lemons also contain other micronutrients like potassium, vitamin B6, and thiamin. Micronutrients are vitamins and minerals needed by your body in small amounts.
Lemons are quite low in calories. Their main nutritional value comes from vitamin C, but they’re also a good source of phenolic compounds and carotenoids. These antioxidants protect against oxidative stress and cell damage linked to chronic disease.
Lemon is generally safe to eat in the amounts you typically find in food and beverages. However, because research is limited, experts are uncertain about the safety of consuming it in medical amounts, such as from a lemon concentrate supplement.
Potential risks include:
- Phototoxicity: Skin exposure to lemon oil may cause phototoxicity, a harmful skin reaction to light.
- Allergies: Some people may have a sensitivity to citrus fruits. Possible reactions range from mild symptoms like itchiness around your mouth to anaphylaxis, a severe and potentially life-threatening situation. Contact a doctor if you think you may be allergic to citrus fruits. They can help you get tested for allergies and receive treatment if necessary.
- Dental erosion: The acid in lemons can break down tooth enamel. It’s best to rinse your mouth with plain water after consuming lemon.
- Gastrointestinal symptoms: Some people with acid reflux or gastroesophageal reflux disease (GERD) find that the acidity of citrus fruits makes their symptoms worse. GERD is a gastrointestinal disorder that occurs when your stomach acid repeatedly flows back into your esophagus (the tube that carries food from your mouth to your stomach).
Adding some lemon to your diet may help you increase your vitamin C intake and antioxidant consumption to support health. Here are some tips to eat more lemons and maximize their freshness:
- Add lemon juice or a lemon wedge to water or tea.
- Marinate meat, fish, or tofu in lemon juice and garnish with lemon slices.
- Make a simple legume (e.g., chickpea) salad with lemon dressing to enhance absorption of nonheme iron.
- Use lemon or lemon zest to add flavor to soups, grains, or pastries.
- Store lemons in the crisper section of your fridge to maximize freshness.
- Freeze cut or whole lemons that you’re not going to use to prevent them from going to waste.
Lemons can add bright flavor and nutritional value to your meals and beverages. They’re packed with vitamin C and antioxidants that promote heart health, help prevent kidney stones and cell damage, and enhance iron absorption.
Some people have a sensitivity to citrus fruits. The acidity of lemons can also erode tooth enamel and cause gastrointestinal symptoms. Pay attention to possible negative side effects of consuming lemons and reach out to your healthcare provider if you have questions or concerns.
