Does Barley Water Break a Fast?
Yes, barley water made by simmering barley generally breaks a calorie-free fast because carbohydrates and calories enter the water. There is no direct evidence cited here on how barley water affects insulin or autophagy during a fast. For a calorie-free fast, choose plain water during the fasting window and save barley water for your eating window.
Does barley water break a fast?
Barley water is usually made by cooking barley in water and straining out the grains. Straining removes the solids, but it does not necessarily remove the carbohydrates that have passed into the liquid. Unsweetened barley water can therefore contain calories even when it looks clear.
If your fast means consuming no calories, drinking barley water ends that fast. This applies even if you do not eat the cooked barley. Adding sugar or other caloric ingredients makes the drink more clearly incompatible with a calorie-free fast, but leaving them out does not make it plain water.
Some fasting plans are less strict and allow certain drinks or small amounts of calories. In that case, barley water might fit the plan's rules, but it still counts as caloric intake. Check the particular plan rather than assuming that every fasting method uses the same definition.
How many calories are in barley water, and does it affect insulin?
There is no single calorie count for barley water. A homemade batch can vary with the amount of barley and water used, how it is prepared, what is strained out and whether anything is added. The calories in the original grains are not automatically the calories in the strained drink.
For a packaged drink, check the nutrition label and serving size. To estimate the calories you consume, multiply the calories per serving by the number of servings you drink. If the label lists zero calories, remember that labeling rules can allow small amounts to be rounded down; a zero-calorie label is not necessarily proof that a drink contains absolutely no calories.
For homemade barley water, an exact calorie count is harder to establish without measuring what remains in the liquid. Do not assume it is calorie-free because it is unsweetened, diluted or strained. If avoiding all calories matters to your fast, the simplest choice is to drink it after the fast ends.
Carbohydrates can raise blood glucose and prompt an insulin response, but the size of any response depends on the amount consumed and the individual. There is no direct evidence cited here establishing how much a particular serving of barley water changes insulin during a fast. Taste and color cannot tell you the response either.
Can you drink barley water for intermittent fasting, a water fast or autophagy?
The answer depends on what your fasting method permits. It also depends on your goal: following a meal schedule is different from consuming only water or trying to maintain a particular cellular process.
Intermittent fasting
If your intermittent fasting plan calls for a calorie-free fasting window, have barley water during the eating window. If your plan permits calories during the fasting window, check its rules and the drink's label; being permitted by a plan is not the same as being calorie-free.
To organize your schedule, mark the end of your last calorie-containing meal as the start of your fasting window and your planned next meal as its end. An intermittent fasting timer can help you track that window. Drinking barley water during it ends a calorie-free fast, even if the rest of your schedule stays the same.
Water fasting
A water-only fast excludes barley water because it is not plain water. Straining the barley or omitting sweetener does not change that distinction. Save the drink until the fast is over.
If you have been told to fast for a blood test, procedure or other medical reason, follow the instructions from your care team. Do not assume that the rules for an intermittent fasting plan apply to a medical fast; ask the team if you are unsure what you may drink.
Fasting for autophagy
Autophagy is a normal process in which cells break down and recycle components. Fasting is often discussed in connection with it, but there is no direct evidence cited here showing what a serving of barley water does to autophagy during a fast.
You cannot tell from a drink's appearance whether it changes autophagy, or determine a personal threshold from the available information. Avoiding barley water may help you keep a calorie-free fast, but it does not guarantee a particular level of autophagy or a health benefit.
When should you check with a clinician?
Ask a clinician before fasting if you are pregnant or breastfeeding, have diabetes or a history of an eating disorder, or take medication that lowers blood sugar or needs to be taken with food. Do not change or stop medication to fit a fasting schedule. If you feel faint or unwell while fasting, stop and seek medical advice; loss of consciousness or severe confusion needs urgent care.
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Intermittent Fasting Timer →Frequently asked questions
Is barley water gluten-free?
No. Barley contains gluten, and strained barley water should not be assumed to be gluten-free. People with celiac disease should avoid it.
Does barley water count toward hydration?
Yes, barley water provides fluid. It can contribute to hydration, although its calories mean it is not equivalent to plain water for a calorie-free fast.
Can I save the cooked barley for a meal?
Yes. Refrigerate the cooked barley promptly and include it in a meal during your eating window.