People are squeezing citrus into their morning brew for weight loss and better skin – but does the science stack up?
Medically reviewed by Dr Roger Henderson and words by Annie Hayes
Some people swear by a freshly brewed cup of coffee to start the day, while others prefer to rise and shine with a refreshing glass of lemon water. Now, the emergence of a new trend sees them consumed together, with claims the tonic has fat-melting, skin-protecting, headache-soothing virtues.
While coffee and lemon have been studied for their health benefits individually, a question mark remains over the merits of combining the two. We spoke to nutritionist and senior personal trainer Luke Hanna to find out whether there’s science behind squeezing citrus into your morning cup of joe.
Coffee with lemon ingredients
For many of us, coffee is an everyday staple. Around two billion cups are enjoyed every morning, according to the British Coffee Association, making it the most popular drink consumed worldwide.
The brewed drink, made from roasted coffee beans, contains a stimulant called caffeine. It’s responsible for improving various aspects of brain function, including memory, concentration and energy levels.
Lemons, meanwhile, are among the world’s most produced citrus fruits. They have been used for their medicinal properties for centuries and are loaded with fibre.
Both coffee and lemons are known to contain high levels of antioxidants, which protect your body from the harmful effects of excessive amounts of free radicals. When combining the two, it’s suggested to add the juice of one lemon to 240ml of coffee.
‘A cup of coffee contains vitamins and minerals such as B12, B5, manganese, potassium, magnesium and niacin,’ says Hanna. ‘Coffee is rich in powerful antioxidants, and one study found many people get more antioxidants from coffee than from fruits and veggies combined.
‘Like many other fruits, lemon can provide us with phytochemicals and are particularly good sources of vitamin C,’ he continues.
Coffee with lemon health benefits
To understand whether drinking coffee with lemon could bring extra health benefits, it’s helpful to consider the two independently.
Coffee health benefits
There are myriad studies touting the wide-ranging health benefits of coffee, that range from protecting your liver to warding off depression.
In one of the largest coffee studies to date, the National Cancer Institute and the National Institutes of Health found that drinking up to seven cups every day could cut your risk of death by 16 per cent.
Regular consumption is associated with a reduced risk of many chronic diseases, says Hanna, including various cancers – specifically breast, colorectal, colon, endometrial, and prostate – heart disease, Parkinson’s, and type 2 diabetes.
That’s not all. When it comes to boosting mental and physical performance, caffeine is one of the most effective supplements around.
‘Benefits include potential increases in strength, muscular endurance, alertness and decreased RPE [rate of perceived exertion], which means you will perceive the workout as less taxing compared to doing the same thing with no caffeine boost,’ says Hanna.
Lemon health benefits
Lemons are a great source of vitamin C and flavonoids, both powerful antioxidants that have been linked to a lower risk of cancers, including oesophagus, stomach, pancreas, and breast cancer.
One lemon provides about 31 mg of vitamin C, which is 51 per cent of your recommended daily intake. Eating fruits and vegetables rich in vitamin C reduces your risk of heart disease and stroke, protects your immune system and helps fight infections.
Coffee with lemon health claims
There are a few health claims surrounding the benefits of drinking coffee with lemon – here, Hanna separates fact from fiction.
Coffee with lemon can help with fat loss
This claim isn’t entirely unfounded. Some studies show that caffeine can help boost your metabolic rate, which will result in more energy burned at rest.
It also stimulates the nervous system, which sends direct signals to the fat cells, telling them to break down fat.
However, this won’t have any effect on fat loss unless you’re in a calorie deficit i.e. burning more calories than you consume each day.
Coffee might support this, too. ‘Anecdotally, a lot of people report appetite-suppressing effects after drinking coffee, which may result in less calories being consumed,’ Hanna says.
How about lemon? Like most fruits, it’s generally healthy, he says. But it ‘has no special, proven advantages when it comes to fat loss.’
In conclusion, there’s no evidence that combining coffee and lemon will provide you with extra fat loss benefits.
Coffee with lemon can ease headaches
This claim is almost entirely unsubstantiated. While some research has shown that high consumption of caffeine can increase the prevalence of headaches, other studies have demonstrated the exact opposite.
‘One study found the frequency of non-migraine headache was 18 per cent more likely in those with high levels of caffeine consumption – equivalent to 500mg per day or more – compared to those with the lowest consumption, around 125mg per day,’ he says.
However, another found that consuming caffeine alongside over the counter pain-relievers, such as ibuprofen, may improve their effectiveness.
‘If you experience regular headaches, it may be worth experimenting with your caffeine intake to see what works for you,’ he says. ‘But there’s no evidence that adding lemon into your coffee will relieve headaches.’
Coffee with lemon supports skin health
‘Good skin health has been shown to be positively associated with fruit and vegetables, says Hanna. ‘However, the exact component in the fruit and vegetables responsible for the observed benefit is unknown.’
The amount of micronutrients you’ll obtain from squeezed lemon juice is minimal, he explains, so if it’s improved skin health you’re seeking, focus on increasing your overall intake of fruits and veggies.
Coffee with lemon side effects
While there’s no evidence that combining coffee and lemon will cause any specific side effects, there are a few things to bear in mind.
Lemon juice is highly acidic and can cause erosion in tooth enamel over time, says Hanna, so it may be helpful to rinse your mouth with water after drinking it.
‘Remember that caffeine has a long half life – around 6 hours – meaning it’ll stay in your system for a long time after consumption,’ he adds. ‘It’s advised to not consume caffeine later than around 3pm, otherwise it may impact your sleep.’
Coffee with lemon: the verdict
Like many people, we also like to start the morning with a cup of joe, so we put the coffee with lemon combination through its paces. The verdict? We rather enjoyed it. Flavour-wise, addition of the lemon brightens the coffee and cuts through the bitterness of the espresso. In terms of texture, the coffee feels fresher and less cloying than our traditional mouth-coating espresso. All in all, we heartily approve.
As for whether you should you be putting lemon juice in your morning brew – well, it’s all down to personal preference. ‘If you enjoy putting lemon in your coffee, then go ahead – but don’t expect anything magical to happen due to the specific combination of the two,’ says Hanna.