Few fruits have such a sunny disposition as lemons. On their own the tart tang can be jarring, but when tamed by flavors sweet or savory, they become the life of the party. They are essential in a wide variety of recipes, beautiful to behold and supply an aroma that has been proven to boost the mood. Not to mention that we have them to thank for lemon cake, lemonade and lemon curd, bless their little lemon hearts.

But beyond the culinary and aromatherapy opportunities that lemons so kindly provide, they have some impressive health skills as well. Is it any surprise? They’re so bright and potent, it somehow makes sense.

While lemons have gained a reputation as miracle fruits capable of leaping tall buildings and curing cancer, we know that lemons, in fact, don’t have legs and thus can’t leap. But as for curing cancer? Well, maybe. Find that out and more in the following roundup of this happy fruit’s potential health benefits.

1. Hinder kidney stones

Lemons, being citrus and all, are high in citric acid ­— a weak organic acid that plays a key role in metabolism. And of all the citrus family, lemons and limes have the highest concentrations of it, constituting as much as 8 percent of the dry weight of these fruits. Citric acid (which is different from ascorbic acid, aka vitamin C) may be helpful for people with kidney stones since it slows the formation of them and stops tiny crystals from clumping together to form bigger ones, explains University Wisconsin-Madison School of Medicine and Public Health. The more citric acid in the urine, the more protection you have against forming “problem” calcium-containing kidney stones. The university recommends a half-cup (4 ounces) of pure lemon juice a day to get the equivalent dose of citric acid that pharmacological therapy would supply.

2. Help maintain body pH

Lemon health benefits alkaline

Proponents of an alkaline diet recommend lemons to balance acids. (Photo: ChamelionsEye/Shutterstock)

The body’s alkaline and acid levels have been a hot topic lately, and although high in citric acid, lemon is considered an alkaline food. The popular thinking is that lemon’s citric acid helps to maintain proper body pH, which, as the theory goes, gets out of whack when too many foods like sugar, red meat and dairy are consumed. Erica Kannall, a registered dietitian and certified health/fitness specialist with the American College of Sports Medicine, notes in SF Gate that the citric acid found in lemons helps to maintain body pH within the ideal range, going as far as to say, “which is beneficial in preventing cancer, heart disease, fatigue, weight gain and a variety of other health issues.” The scientific jury is still out on proving the efficacy of alkaline-inspired diet plans, but there is some evidence that there could be certain benefits to eating a more alkaline, produce-rich diet. 

3. Provide protection against disease

Lemons are rich in beta-crypotoxanthin, a pro-vitamin A carotenoid that is converted to an active form of vitamin A in the body. Multiple recent studies have suggested that beta-cryptoxanthin protects against certain diseases such as cardiovascular disease and osteoporosis.

4. Reduce risk of inflammatory disorders

A study in the American Journal of Clinical Nutrition also cites beta-crypotoxanthin as a potential factor in reducing the risk of developing inflammatory disorders such as rheumatoid arthritis.

5. Help absorb antioxidants
Everyone wants more antioxidants, the free-radical-fighting darlings of contemporary health and wellness. According to a digestive model study published in Molecular Nutrition and Food Research, adding fresh lemon juice to green tea, which is already rich in these health-giving compounds, helps increase the absorption of antioxidants.

6. Ease symptoms of the common cold
While lemon isn’t top banana, so to speak, it still has plenty of vitamin C content, which may play a role in dealing with the common cold. There have been a lot of myth-versus-fact stories written about vitamin C and its effect on the cold, but the National Institutes of Health lays it out like this:

  • For most people, vitamin C supplements or vitamin C-rich foods do not reduce the risk of getting the common cold.
  • Taking a vitamin C supplement or [vitamin C-rich foods] after a cold starts does not appear to be helpful.
  • However, people who take vitamin C supplements [or vitamin C-rich foods] regularly might have slightly shorter colds or somewhat milder symptoms.
7. Prevent vitamin C deficiency-related symptoms

The National Institutes of Health also notes that too little vitamin C can lead to deficiency with far-reaching effects, such as:

  • Anemia
  • Bleeding gums
  • Decreased ability to fight infection
  • Decreased wound-healing rate
  • Dry and splitting hair
  • Easy bruising
  • Gingivitis 
  • Nosebleeds
  • Possible weight gain because of slowed metabolism
  • Rough, dry, scaly skin
  • Swollen and painful joints
  • Weakened tooth enamel
8. Keep the dreaded scurvy at bay!

Health benefits lemons

Drink fresh lemonade, skip the scurvy. (Photo: Sofiaworld/Shutterstock)

Long before the British navy figured out that eating oranges and lemons cured scurvy, sailors sailing the Seven Seas often suffered the debilitating effects of this severe form of vitamin C deficiency. It still affects some, but generally only older, malnourished adults. Symptoms of scurvy include constant fatigue, irritability and misery, pain in the limbs, swollen bleeding gums, loose teeth, falling-out teeth, severe pain in joints, bleeding inside joints, bulging eyes, bleeding eyes, failure of wounds to heal, easy bruising, jaundice, edema and potentially fatal heart problems. (Note to self: eat lemons, now.)

9. Prevent weight gain
A study published in the Journal of Clinical Biochemistry and Nutrition concluded that lemon polyphenols ­— an antioxidant found in — slowed weight gain in lab animals. An increase in lemon polyphenols also showed improvements in blood glucose control and insulin function.

10. But can they cure cancer?
There has been a lot of hoopla about lemon’s ability to cure cancer, one viral email claims lemons are, “10,000 times stronger than chemotherapy.” Alas, it’s a myth that gives lemons more superpowers than they've been proven to possess. Some studies have concluded that lemons and their citrus cousins contain naturally occurring substances — mainly modified citrus pectin and limonoids — that may have cancer-fighting properties. The research has found that at very high levels, these compounds are capable of slowing cancer cell growth and inducing cell death in animals and in vitro human breast cancer cultures; but given the parameters of the research, it can’t be concluded that the same is true for humans. More research needs to be conducted and clinical trials will be required before lemons can be confirmed as a cure for cancer. But nonetheless, the findings are promising and they speak to the potent potential of this bright fruit.

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