Lemon juice has a pH level of around 2, making it just as acidic as vinegar. (For comparison, plain H2O has a neutral score of 7.) The low pH means that sipping on the citrus can wear away at your enamel, your teeth’s protective coating. Over time, this ups your risk of cavities and discoloration.
But when the juice is diluted in water, it’s much less of a concern, notes Robin Foroutan, RD, New York City-based integrative dietician at The Morrison Center and a spokesperson for the Academy of Nutrition and Dietetics. Squeeze the juice into water and the mixture’s pH rises to a less damaging 5 or 6. “As long as you’re not drinking lemon juice straight or swishing it around in your mouth, you’re fine,” Foroutan says.
An often overlooked concern is that the juice’s acid causes plastic to leach. As a result, you could wind up ingesting more chemical plasticizers, Foroutan says, which can disrupt your hormones. This is particularly problematic if you buy pre-packaged lemon water or squeeze the juice into your reusable plastic bottle.
If you’re averse to plain water, adding natural flavors may encourage you to drink more. “Most of us walk around in a mild state of dehydration,” Foroutan explains, especially busy people who might be too preoccupied to prioritize sipping.
Lemon water's biggest benefits likely come from the fact that the fruit is alkaline-forming, which helps balance acidity in the body. “Consuming more alkaline foods and beverages may reduce the risk of fractures, preserve muscle mass, protect against chronic disease, and improve memory and cognitive function,” Foroutan says.
Adding them into your diet also reverses the low-grade metabolic acidosis—when your body pulls minerals from the bone to maintain a neutral pH—caused by high-protein diets like paleo or keto. (Over time, the condition can make you more susceptible to kidney stones, reduced bone mineral density, and muscle loss.)
Plus, alkaline foods help to prevent inflammation, thus improving your ability to recover between bouts of high-intensity exercise, says Bethany Snodgrass, holistic health coach and operations manager at the Equinox Fitness Training Institute in New York City.
Lemon water likely has beauty benefits, too, says Sarah Garland, senior manager of spa planning at Equinox in New York City. “It boosts hydration and adds vitamin C to the body, which aids in maintaining and building collagen.” The antioxidants fight acne and free radical damage, she adds.
Lemon water’s benefits outweigh any perceived risks, mostly because of its alkaline properties, the experts agree. Use organic lemons whenever possible and clean the skin if you drop slices into your drink, reminds Garland.
To avoid plastic leaching, mix your own lemon water instead of buying it bottled and use only glass containers. Snodgrass recommends squeezing juice from a quarter lemon into 16 ounces of H2O. If you’re worried about your enamel, drink from a metal or paper straw or further dilute the mixture.