Lemon: Nutritional Facts and Health Benefits

Lemon (Citrus limon) is a citrus fruit that grows in the evergreen tree belonging to the family Rustaceae. It is native to Asia, especially in the Northwestern Indian region. 

Although the plant is evergreen, the fruit is obtained in only a particular season, i.e., late winter to spring. The fruit is yellow colored and used for culinary purposes. (1)

The main extractants from the fruit are its juice and oils. Traditional medicines use the fruit’s oils and juices. (1)

The fruit is nutritionally dense because it has many minerals and vitamins. Since it is a citrus fruit, it is a good source of vitamin C. (2)

Lemon adds flavor to baked foods, salad dressings, sauces, drinks, desserts, and marinades. It is also used in the cosmetic and pharmacy industries. (1)

Nutritional Facts

Lemons are nutritionally rich fruits. Besides minerals and vitamins, the fruit contains bioactive compounds like flavonoids like eriodictyol, quercetin, apigenin, hesperetin, diosmin, and naringin. (1)

The water content in lemon is high, 89 g per 100 g. The exact amount of lemon also provides 29 Kcal energy. It has a low carbohydrate (9.32 g/100 g) and total fat amount (0.3 g/100 g). Protein and total dietary fiber in lemons are also common (100 g of lemon has 1.1 g and 2.8 g, respectively). (2,3) 

Name	Amount in Lemon (raw without peel)	Daily Requirements for Adults
Water	89 g
Energy	29 Kcal	2000-2,500 Kcal
Protein	1.1 g	50-70 g*
Total fat	0.3 g	60-80 g
Carbohydrate	9.32 g	300-375 g
Total dietary fiber	2.8 g	25-30 g

*National Academy of Medicine recommends that adults get a minimum of 0.8 grams of protein for every kilogram of body weight per day. 

Vitamins

As mentioned earlier, lemons are citrus fruits, so it is rich in ascorbic acid. 100 g of lemons has 54 mg of vitamin C. Other vitamins present in good amounts in lemons are vitamin A, folate, and choline. (2,3)

100 g of lemons have one mcg of vitamin A, 11 mcg of folate, and 5.1 mg of choline. (2) The fruit also has some other vitamins; thiamin, vitamin E, vitamin B6, niacin, riboflavin, and pantothenic acid. (2) Other components found in lemons are cryptoxanthin, carotene alpha and beta, and lutein and zeaxanthin. (2)

Name	Amount	Daily Requirements for Adults
Vitamin A	1 mcg	700 mcg – 900 mcg
Folate (Folic acid; vitamin B9)	11 mcg	400 mcg
Vitamin C	54 mg	75 mg -90 mg*
Choline	5.1 mg	425 mg – 550 mg*

*Adequate intake (AI) level determined by National Academy of Medicine. 

Minerals

Lemons have a good amount of calcium, magnesium, potassium, phosphorus, and sodium. 100 g of lemons have 26 mg of calcium, 138 mg of potassium, 2 mg of sodium, 16 mg of phosphorus, and 8 mg of magnesium. (2)

Other minerals present in trace amounts in lemons are iron, zinc, copper, manganese, selenium, copper, and zinc. (2)

Name	Amount	Daily Requirements for Adults
Calcium, Ca	26 mg	1,000 – 1,200 mg
Magnesium, Mg	8 mg	310-420 mg
Phosphorous, P	16 mg	700 mg
Potassium, K	138 mg	2,600 – 3,400 mg*
Sodium, Na	2 mg	<2,300 mg*

*Adequate intake level determined by National Academy of Medicine. 

Other components in lemons are limonoids like nomilin and limonin and phenolic acids like p-hydroxybenzoic acid, synapic acid, dihydro ferulic acid, and 3-propanoic acid. (1) Lemons also have coumarins citropten and scopoletin, furanocoumarins like bergamottin, and carboxylic acids like galacturonic acid, glutaric acid, citric acid, isocitric acid, malic acid, 3-hydroxymethyl glutaric acid, and quinic acid. (1)

The amino acids in lemon fruit are L-alanine, L-asparagine, L-aspartic acid, dimethylglycine, L-phenylalanine, glutamic acid, L-valine, L-tryptophan, L-tyrosine, L-arginine, and DL-proline. (1)

Health Benefits

The nutritionally dense fruit, lemons, are equally beneficial to human health. Different articles have shown that consuming lemons for an extended period can help maintain health. Its consumption is helpful as a detoxifying agent for weight loss. 

Likewise, the effect of lemon consumption is advantageous for heart health, intestinal microbiome, and healthy aging. A brief description of the health benefits of the consumption and use of lemons are as follows:

1. Antioxidant activity: Oxidative stress can produce excessive oxygen, which can long-term affect human health, especially human skin. Consumption of citrus-based juice like lemon showed increased expression of antioxidant enzymes like glutathione reductase, manganese superoxide dismutase, and catalase. (4) 
2. Effective against aging: Effects like wrinkling and skin thickening can be reduced if a citrus-based juice mixture, including lemon juice, is administered orally in mice. (4) 
3. Can help reduce weight: Using a lemon detox program where a low-calorie diet combined with maple syrup, palm syrups, and lemon juice helped minimize body fat in a study conducted in eighty-four premenopausal overweight Korean women. (5) It also helps reduce insulin resistance, which benefits cardiovascular disease. (5) 
4. May help control blood pressure: Lemon consumption and walking can help control blood pressure. A study on 101 middle-aged women on the island of Hiroshima, Japan, showed that combining lemon juice consumption with walking can greatly influence lowering of systolic blood pressure. (6) It also had a good amount of potassium. A study suggests that adequate potassium intake helps lower blood pressure levels. However, excessive consumption of potassium should be avoided. (7)
5. Can reduce glycemic response: Lemon juice has decreased the glycemic response to starchy foods. A study that observed the glycemic response to bread consumed with tea, water, or lemon juice reported that lemon juice lowered the glycemic response. (8) The reduction may be due to the hydrolysis of starch by acid inhibition by salivary amylase. (8)
6. Aromatic therapy: Limonene present in the lemon can be used as aromatic fragnance in cosmetic industries. The limonene has been known to have anti-inflammatory activities, anti-hyperalgesic, gastroprotective, anti-diabetic, antinociceptive, and antiviral effects. So, it is used as phytomedicine. (9)