Lemon water in the morning is popular, but is it good for you - and the best way to have lemons? Photo / 123rf
This citrus fruit has a whole host of health benefits that go beyond just vitamin C.
When the United Kingdom Royal Navy introduced a cure for scurvy in 1795 it was lemon juice, not limes that were first given to sailors. That Britons became known as Limeys, rather than perhaps Lemoneys, was down to good old cost saving: lime juice sourced from British possessions in the Caribbean turned out to be cheaper, if not quite as effective as lemons.
Still, for as long as we’ve understood that vitamin C is important for our health, lemons have been recognised as a good source of it. And recently, freshly squeezed lemon juice mixed with warm water, often taken first thing in the morning in place of tea or coffee, has become a fashionably healthy lifestyle choice.
So should we be swigging a lemon water before we even think about a coffee or tea, and what are the other health benefits of lemons?
As well as being hydrating, drinking lemon water in the morning may promote digestion.
“While the research is limited, there is some logic behind it,” says VJ Hamilton, a registered nutritionist and autoimmunity specialist. “The acidity of lemon juice can help stimulate stomach acid production, which is important for breaking down food and absorbing nutrients.”
Additionally, if you’re not a fan of the plain stuff, warm lemon water can encourage hydration, which is crucial for keeping digestion regular, says Hamilton.
“Lemon water can encourage fluid intake and can make drinking water more enjoyable. Some of my clients also find it helps with bloating or constipation.”
Lemons are a nutrient-rich fruit, primarily known for their high vitamin C content. According to Nichola Ludlam-Raine, a dietitian and the author of How Not to Eat Ultra-Processed, they also contain small amounts of potassium, vitamin B6, folate and magnesium, all of which are “important for heart health and muscle function, metabolism and bone health”.
And while they might not be as packed with antioxidants as berries or leafy greens, the vitamin C in lemons helps protect cells from oxidative stress and supports immune function.
Alongside vitamin C, lemons are a great source of other antioxidants. “They also contain flavonoids like hesperidin and eriocitrin, which have been shown to have anti-inflammatory and heart-protective effects,” says Hamilton.
Lemons can support immune health, but they’re not a magic shield against illness. “Their high vitamin C content plays a role in immune function and has been shown to slightly reduce the duration of colds,” says Hamilton.
Beyond immune support, lemons are often associated with detoxification. “While the body naturally detoxifies through the liver and kidneys, compounds in lemons – particularly vitamin C and citric acid – can support these processes,” says Hamilton. Research shows that citric acid may enhance enzyme function in the liver, aiding the body’s ability to break down toxins.
Lemons may also contribute to kidney and heart health. “Their citric acid content can help prevent kidney stone formation, while their flavonoids have been studied for their potential role in supporting blood vessel function and circulation,” says Hamilton.
They also support heart health: “The flavonoids in lemons help reduce blood pressure and cholesterol levels”, says Ludlam Raine.
Lemon water can also improve skin health: “Vitamin C is crucial for collagen production, promoting healthy, glowing skin”, says Ludlam-Raine.
Some animal studies also show that drinking lemon water may help prevent oxidative stress, which can lead to premature skin ageing. Because vitamin C is an antioxidant, it could also help prevent the free radicals that break down collagen. More research is needed, however.
Eating vitamin C-rich foods during meals to help increase the absorption of non-heme iron. Non-heme iron is mainly found in plant foods, but your body has a harder time absorbing it.
“Consuming lemons with iron-rich foods like spinach or lentils can increase iron absorption and help prevent anaemia as a result of the vitamin C content,” says Ludlam-Raine.
This is particularly important if you are following a plant-based diet.
Hamilton adds: “It’s also an excellent way to lift plant-based dishes – stirring zest into quinoa, for example, adds a fresh, citrusy depth that pairs well with herbs and extra virgin olive oil”.
Different parts of the fruit contain different beneficial compounds.
“The juice is rich in vitamin C and citric acid, which support immune function, digestion, and kidney health. Meanwhile, the zest is packed with flavonoids, pectin, and essential oils like limonene, which offer antioxidant and anti-inflammatory benefits,” says Hamilton.
For a concentrated immune-supporting hit, Hamilton recommends using lemons in homemade booster shots, blended with ingredients like ginger, cayenne, and turmeric.
“Ginger and cayenne both have anti-inflammatory properties, while turmeric contains curcumin, which has been studied for its immune-supporting effects. Together, they create a powerful combination that helps fight oxidative stress and supports circulation.”
For those who prefer a gentler option, adding lemon to herbal teas or broths can be a soothing way to enjoy its benefits without too much acidity. “Warm lemon water with honey and ginger is also a classic remedy for colds and sore throats, offering a mix of hydration, antioxidants, and antimicrobial properties,” says Hamilton.
Lemon zest is great sprinkled over grilled fish, stirred into quinoa or wild rice, or added to dressings and marinades. Lemon juice also works well in sauces, soups, and roasted vegetables, helping to brighten flavours and improve the absorption of certain nutrients.
“Pairing lemon juice with olive oil and herbs can enhance the absorption of fat-soluble vitamins, while using it in marinades helps tenderise proteins and boost flavour without the need for excessive salt,” says Hamilton.
Lemons are generally well tolerated, but in some cases, they can cause sensitivities or allergic reactions. “True citrus allergies are rare but they can trigger itching, swelling, hives, or, in severe cases, anaphylaxis,” says Hamilton.
More commonly, people experience irritation rather than an actual allergy: “Lemons are highly acidic, which can cause mouth tingling or discomfort, particularly in those with conditions like oral allergy syndrome or acid reflux. Their acidity can also be a trigger for heartburn, making them problematic for some people with gastroesophageal reflux disease,” says Hamilton.
Another factor to consider is that while lemons aren’t high in histamine, they can act as histamine liberators, meaning they encourage the body to release stored histamine.
“This can be an issue for those with histamine intolerance or mast cell activation syndrome, where the body struggles to break down histamine efficiently because of its low levels of diamine oxidase, the enzyme responsible for histamine breakdown.” explains Hamilton.
When histamine builds up, it can lead to symptoms such as headaches, itching, flushing, and digestive discomfort.
Lemon zest, while rich in antioxidants and flavour-enhancing compounds, can also cause skin irritation in some people because of its essential oil content. “In rare cases, handling lemon juice or peel in sunlight can lead to phytophotodermatitis, a skin reaction that causes redness, blistering, or dark patches,” says Hamilton.
While lemons have plenty of health benefits, they do come with a few potential downsides, mainly as a result of their acidity. One of the biggest concerns is dental health.
“Lemon juice is highly acidic and can wear down tooth enamel over time, leading to sensitivity and a higher risk of cavities,” says Hamilton. “Sipping on lemon water all day can make this worse, so it’s best to drink it through a straw and rinse your mouth with water afterwards to help protect your teeth.