Intermittent fasting has become a very popular weight loss technique over the last decade. During that time there has been a lot of research supporting the benefits of intermittent fasting in terms of not just weight loss, but also overall health benefits.
Intermittent fasting involves dividing your day into a fasting period and an eating window. During the period of fasting, you only drink water.
Plain water, while it is the very best liquid you can consume, can be quite boring. As a result, people like to give it a bit of flavor. One way to do that is to add some lemon juice to it.
Does Lemon Break a Fast?
This gives rise to the question of whether lemon water will break a fast. The answer is that it depends on the reason that you’re fasting in the first place.
If your primary reason for fasting is to lose weight, then adding some lemon juice to your water will not break the fast. But if you are mainly fasting to health your gut issues, then, lemon water will break the fast.
Why Add Lemons to Your Water?
The main reason that you would want to add lemon to your water is obvious – it breaks the boredom of drinking plain water during your fast. But there are other reasons.
Lemons are a very nutritious food. They are high in fiber, and vitamin c, and rich in antioxidants and other compounds that promote the immune system. The combination of fiber and vitamin c in lemons has been shown to improve heart health.
Two compounds that are in lemons, diosmin, and hesperidin, have been shown to lower cholesterol levels. 
Lemons can also help to promote weight loss. This is thought to be due to the expansion of pectin fiber in your gut which promotes a feeling of fullness. That is a huge benefit when you are intermittent fasting. 
Lemons have been shown to assist in the digestive process, helping you to convert ingested food into energy more efficiently and aid in elimination.
A final benefit of adding lemon to your water is that it promotes healthy, glowing skin.
Does Lemon Water Affect a Weight Loss Fast?
A key reason that people fast is to cut out carbohydrate intake. Carbs represent the body’s main source of fuel for energy. When you restrict carbs, your body is forced to switch to stored body fat as its energy source. As a result, you will lose body fat.
A whole lemon contains just two grams of carbohydrates. That is not enough to spike your insulin levels. Nor is it enough to break your fast.
Of course, you won’t be eating the whole lemon during your fast. You will simply be squeezing the juice of the lemon into your water to create a plain lemon water beverage.
Many intermittent faster find that having a water bottle’s quantity of plain lemon water first thing in the morning while they are in the middle of a 16/8 fast gives them an immediate energy boost, and helps them to stay on track without feeling hungry.
The lemon in your water will help fill you up, help you overcome the boredom of having to chug plain water, and provides you with health-giving vitamin c and fiber.
Does Lemon Water Affect a Gut Health Fast?
When you are doing a fast to heal your gut, your key objective is to shut down the digestive process to allow time for the gut to clean, detoxify and heal itself.
Your body has its own inbuilt gut-cleaning mechanism. it is called the migrating motor complex (MMC). 
The Vital Role of the MMC
The MMC encourages peristalsis. This is the movement of your intestinal muscles that assist you to transport food through your digestive tract.
The MMC helps to keep us regular by eliminating waste products from the body. It also assists in the prevention of illnesses and bacterial overgrowth in the stomach.
Maintaining the health of your digestive tract depends heavily on the MMC’s cleansing functions.
There’s a catch, though!
The migrating motor complex only operates when you are not eating. Your body must concentrate solely on breaking down food during digestion.
It can take up to four hours for the MMC to complete its cycle. If you eat any food during that time, you will shut down the process. While water will not stop this process, anything added to water will.
And that includes lemon juice!
So, if you are wanting to get the maximum gut cleansing benefits of intermittent fasting, you should not add lemon juice to your water. The same thing applies to black coffee. In a similar way to lemon water, black coffee will not negatively affect your weight loss fast. But it will put a stop to the migrating motor complex.
How Many Lemons Can You Add?
As previously mentioned, there are about two grams of carbs in a whole lemon. The average lemon will also contain about 29 calories. Even though those are very low numbers, they will, from a technical standpoint, break a fast.
However, you will not be adding the entire lemon to your fasting diet. Instead, you’ll be simply adding lemon juice to your plain water. This could be by dropping a slice of lemon into the water or by actually squeezing the juice directly into the water.
When you add the juice of the lemon to your water, you will be adding less than a single carbohydrate. a tablespoon of lemon juice contains around three calories. That is probably about how much you would add to a bottle of water.
Those small amounts will not negatively impact your weight loss fasting efforts. In fact, as we have already covered, they will help you to stay on track by reducing the boredom of drinking plain water. Lemon juice also promotes a feeling of fullness and boosts the immune system.
Frequently Asked Questions
Is lemon water good for you?
Yes, adding lemon to your water has been shown to have a number of health benefits. These include improving digestive health, reducing insulin sensitivity, improving got health, and promoting a feeling of fullness.
What other liquids can you consume during a fast?
If you are doing a fast for weight loss, you will be only able to consume beverages that do not contain any carbs. Depending on how strict you want the fast to be, you may also be able to consume drinks that have very low calories but no carbohydrates.
Some beverages that are consumed by people during a fasting period are apple cider vinegar, warm lemon water, black coffee, and carbonated plain water. You should avoid sports drinks, white tea, fruit juices, vegetable juice, and a cup of coffee with milk or sugar added.
What type of lemon water should you use when intermittent fasting?
I recommend actually squeezing the juice from a lemon rather than buying bottled lemon juice, You can also put lemon slices in your water bottle.
How many grams of protein and carbs are in a lemon?
An average-sized lemon will have around 2 grams of carbohydrates and one gram of protein. The carbohydrates are in the form of two grams of sugar (fructose). There are approximately 28 calories in an average lemon.
Adding lemon juice to your water helps to make your beverage tastier and promotes a feeling of fullness. If you are fasting for weight loss, the addition of lemon to your water will not break your fast.
However, if your main fasting goal is to cleanse and detoxify your gut, lemon water will stop the migrating motor complex, which is the body’s internal cleansing system.
It all comes down to what your fasting goal is.
- Fukuchi Y, Hiramitsu M, Okada M, Hayashi S, Nabeno Y, Osawa T, Naito M. Lemon Polyphenols Suppress Diet-induced Obesity by Up-Regulation of mRNA Levels of the Enzymes Involved in beta-Oxidation in Mouse White Adipose Tissue. J Clin Biochem Nutr. 2008 Nov;43(3):201-9. doi: 10.3164/jcbn.2008066. Epub 2008 Oct 31. PMID: 19015756; PMCID: PMC2581754.
- Alam MA, Subhan N, Rahman MM, Uddin SJ, Reza HM, Sarker SD. Effect of citrus flavonoids, naringin and naringenin, on metabolic syndrome and their mechanisms of action. Adv Nutr. 2014 Jul 14;5(4):404-17. doi: 10.3945/an.113.005603. PMID: 25022990; PMCID: PMC4085189.
- Deloose E, Janssen P, Depoortere I, Tack J. The migrating motor complex: control mechanisms and its role in health and disease. Nat Rev Gastroenterol Hepatol. 2012 Mar 27;9(5):271-85. doi: 10.1038/nrgastro.2012.57. PMID: 22450306.