Ask a Dietitian

Lemon water has been recommended for years as part of weight loss plans, touted for its’ ability to detoxify, alkalinize, boost IQ, mood and energy, boost immune function, prevent kidney stones and aid digestion.  But does the science really support all these claims?

What is lemon water?

It’s just that.  Fresh lemon juice squeezed into a glass of water.  Occasionally garnished with mint or the rind or flavoured with ginger and served either hot or cold.  If you use ½ a lemon and 1 cup of water you will get about 9 calories, 2 grams of carbs and 25% DRI of Vitamin C.  It also contains small amount of bioactive ingredients such as citric acid, hesperidin and a molecule called D-limonene (in the peel).

Weight Loss

Water is known to help reduce food consumption for older adults when consumed before a meal.  Water does help to fill you up and may aid in weight loss.  Lemon water is virtually calorie free so if consuming it helps to reduce calorie consumption then it may help with weight loss.  But not because of the lemon, but maybe just the lemony taste helps you remember to drink it.

Detoxification of the Liver

Water helps with waste removal from the body via urine and feces.  Adding lemon does not improve this.  There is a molecule called D-limonene in the rind of a lemon which may affect detoxification enzymes in the liver but you would likely need the essential oil from the skin, not just a squeeze of lemon in water.  More research is needed to determine quantities and exact effect on these enzymes.

Alkalinisation

There are so many things that claim to alkalinize the body, in the hopes of increasing the pH and fighting cancer cells.  Research shows that neither the pH of your blood or your cells can be altered by what you eat.  Blood pH is tightly regulated by our body and good thing because conditions such as ketoacidosis can lead to death.

Boost IQ, Mood and Energy

There are claims that drinking a glass of lemon water in the morning boosts IQ and perks you up. Hydration does help improve mental focus, visual acuity, mood, memory and performance in sport.  There is no evidence of these being enhanced with lemon water.  A deficiency in Vitamin C treated with vitamin C from foods can improve mood.  Lemon oil may improve mood.

Boost Immune Function

There is vitamin C in lemons and although Vitamin C does not prevent the common cold, it has been shown to reduce the duration and symptoms.  Hopefully you aren’t relying on lemon water for your only source vitamin C.  You get loads in kiwi, strawberries, papaya, peppers, broccoli and oranges.

Prevent Kidney Stones

Lemons are an excellent source of citric acid which when consumed can bind calcium in the urine and prevent kidney stone formation.  1 point for Lemon water.  Whoot! Whoot!

Aid Digestion

Bile acids help with fat digestion and we produce enough when we eat a fatty meal that we don’t need lemons to help.  We also produce enough HCl in our stomach to digest our food that the acidity of lemons is not needed.  However, the acidity from lemon water could slow gastric emptying which in turn will allow nutrients more time to be absorbed so it could help with improving nutrient absorption. Water helps prevent constipation, no need for lemon for that.

Risks

The risk of consuming lemon water too often is the constant exposure of acid to the teeth which will erode tooth enamel.  Drinking through a straw can help reduce exposure as can rinsing your mouth after drinking.  It is not recommended to brush your teeth after exposing teeth to the acid from lemon water.  You are better off rinsing or chewing sugar free gum.