Fruits
Known for adding flavour, freshness, and acidity to drinks and foods, lemons are the most commonly used citrus fruits. Lemons are also used for garnish and flavouring desserts. They can be juiced, cut into wedges, or grated to make lemon zest.
This versatile fruit is an excellent source of vitamin C. They are naturally low in calories and carbohydrates and available all year long. Lemons are a perfect fruit to keep on hand for salad dressings, seafood recipes, flavouring water, and more.
Lemon Nutrition Facts
The following nutrition information is provided by the USDA for one lemon (without rind) measuring approximately 2 1/8" in diameter (58g).
Calories: 17
Fat: 0.2g
Sodium: 1mg
Carbohydrates: 5.4g
Fibre: 1.6g
Sugars: 1.5g
Protein: 0.6g
Carbs
One whole lemon contains 17 calories and just over 5 grams of carbohydrate. The carbs are primarily fibre (1.6 grams) and sugar (1.5 grams). Note that the juice of a whole lemon provides only 0.14 grams of fibre, according to USDA data, but almost the same amount of sugar.
The glycemic load of a whole lemon is estimated to be 1, making it a low-glycemic food.
Fats
There is a very small amount of fat in lemons, under 1 gram if you consume the whole fruit.
Protein
Lemons are not a good source of protein, providing less than 1 gram per fruit.
Vitamins and Minerals
Lemons are an excellent source of vitamin C, providing over half (30.7mg) of your daily recommended intake. There are also very small amounts of thiamin, vitamin B6, and folate in lemon.
Lemons are not a good source of minerals, but they do contain small amounts of calcium, iron, and potassium.
Health Benefits
The health benefits of lemons are attributed primarily to the high level of vitamin C that the fruit provides.
Prevents Deficiency
Lemons have been used throughout history to manage vitamin C deficiency.
In the late 1700s, the British Navy discovered that scurvy, a disease caused by vitamin C deficiency, could be cured by eating lemons and oranges. Today, scurvy is a rare disease in developed countries, given that it can be prevented with as little as 10mg of vitamin C.
Improved Heart Health
Studies indicate that a higher intake of vitamin C is associated with a reduced risk of cardiovascular disease (CVD), including coronary heart disease and stroke. The National Institutes of Health states that the benefit is likely due to the antioxidant content of lemon which helps to prevent oxidative damage that can lead to cardiovascular disease.
But authors of one large review were careful to put their findings into perspective. They concluded that while research suggests that vitamin C deficiency is associated with a higher risk of death from cardiovascular disease and that vitamin C may slightly improve endothelial function and lipid profiles in some groups, studies do not provide enough support for the widespread use of vitamin C supplementation to reduce cardiovascular risk or mortality.
Slower Age-Related Decline
Vitamin C is a powerful antioxidant. Antioxidants help to prevent cell damage caused by oxidative stress. There is ongoing research about the possible impact that antioxidants can have on the aging process. There is some evidence that they may help improve skin health or even help prevent certain types of diseases associated with ageing. So far, however, study results have been mixed.
Improved Eye Health
Additionally, researchers are investigating whether a higher intake of vitamin C can help treat or prevent age-related macular degeneration (AMD) and cataracts—common causes of vision decline in older adults. So far, study results have been inconsistent but research is ongoing.
Better Immune Function
Vitamin C has been shown to play an important role in immune function. In fact, many use vitamin C to prevent or manage the treatment of the common cold.
Studies investigating whether or not vitamin C can really help treat or prevent the cold have yielded mixed results. A few large studies have shown that taking about 250 mg per day may help certain specific populations reduce the incidence of colds, but other studies have shown no benefit in the general population.
Cancer Prevention
Antioxidants, such as those in lemon, are being investigated for their potential impact on cancer.
According to the National Cancer Institute, increased levels of antioxidants may be able to prevent the types of free radical damage that have been associated with cancer development. Free radicals are chemicals that can cause cellular damage in the body. Exposure to certain environmental toxins (like cigarette smoke) may increase the free radicals in your body and even cause the body to make more free radicals.
But researchers still don't know if antioxidants have the power to combat or prevent cancer. More research needs to be done investigating the impact of antioxidants from food versus antioxidant supplements. For now, there is not enough evidence to know for sure if there is any benefit.
Allergies
People with an allergy to citrus fruits should avoid lemon or products made with lemon or lemon zest. Citrus allergy is not common but can be problematic in some people.
There are also reports of asthma as a reaction to inhalation of lemon or orange peel. If you suspect an allergy to lemon, seek care from a qualified allergy specialist.
Adverse Effects
The acid in lemon juice can strip the enamel on teeth, making them weak and sensitive. If you tend to drink water with lemon often, using a straw can reduce the exposure of acid to your teeth.
According to the Natural Medicines Database, it is not known if there are drug interactions with lemon. However, one study indicated that there may be a positive impact on certain nuclear imaging tests when men ingest lemon juice prior to testing.
Varieties
There are many different types of lemons. Most are bright yellow, but some have a green hue. Interestingly, one of the most common varieties—the Meyer lemon—is not a true lemon, but a cross between a lemon and a mandarin or orange.
The lemons you buy at the grocery store are likely to be Lisbon, Bearss, or Eureka.
When It’s Best
Most lemons can be found in the grocery all year round. Many growers harvest their fruit year-round, but the peak harvest season is late winter to early spring or summer.
When picking lemons, look for lemons that have thin skin as this is an indicator of juiciness. Lemons should feel heavy for their size and appear bright, vibrant yellow, and have a smooth, blemish-free surface. Avoid lemons that are soft and spongy or have wrinkled skin.
Storage and Food Safety
Many people store lemons on the countertop to take advantage of their bright, beautiful colour. But if you keep lemons out at room temperature, they are likely to last only for about a week.
To help them last longer, store lemons in the refrigerator. Some people place them in a bowl of water, but you can also place them in a plastic bag for optimal shelf life. Stored properly, they should last about 2 to 3 weeks.
Lemons can also be frozen. Freeze whole lemons, lemon wedges, or lemon juice in freezer bags with as much air removed as possible.
Lemons can also help your other foods last longer. Certain fresh produce, such as apples, turn brown when they begin to oxidise. The process is referred to as enzymatic browning and occurs when certain enzymes and chemicals, known as phenolic compounds, combine and react to oxygen. The brown pigment, melanin, is completely harmless but not very appealing.
Other foods, such as pears, bananas, avocado, eggplants, and potatoes also undergo enzymatic browning. The acidic nature of lemon juice prevents browning by denaturing the enzymes. To make these foods last longer, rub lemon or lemon juice on any exposed part of the fruit.
How to Prepare
You can eat a whole lemon, but you probably won't want to. Their intense sour flavour makes them difficult to eat on their own. Instead, use lemons to add colour and flavour to all different types of cuisines and meal types.
Make your own salad dressing, using lemon juice as a nutritious way to reduce your sodium and calorie intake. Spice up your vegetables with a lemony sauce. Cut up lemon wedges or slices to flavour your water or seltzer, use lemon juice in fruit salads to prevent browning, or as an ingredient in marinades to tenderise meat.
Lemons and lemon juice can also be an important ingredient in making healthier dessert options. Just be sure to choose recipes that are lower in added sugar if you are watching your carb intake.
Be sure to utilise the whole lemon, using the skin for lemon zest (the yellow, outer skin). To zest a lemon, use a peeler or a grater taking care not to cut the bitter inner white skin, called the pith.
