Intermittent fasting is one of the most popular health trends thanks to its many proposed health benefits, including weight loss, fat burning, and reduced inflammation (1).

This dietary pattern involves alternating cycles of fasting and eating. Unlike traditional diets, no foods are banned during the eating periods.

Still, you may wonder whether alcohol diminishes any benefits of intermittent fasting.

This article examines how alcohol affects intermittent fasting and reviews whether certain drinks are better than others.

Intermittent fasting may boost fat burning, thus decreasing your body fat percentage (2).

Yet, alcohol intake has been shown to block fat breakdown.

In one study in 19 adults, ingesting an alcohol-rich meal resulted in significantly reduced levels of fat breakdown 5 hours after eating, compared with a meal rich in protein, fat, and carbs (3).

Alcohol may also stimulate overeating, which can lead to weight gain over time (4).

In observational studies, excessive alcohol consumption is associated with increased levels of body fat. However, this relationship does not appear in light to moderate drinkers (5, 6).

More evidence is needed to understand how alcohol affects body weight.

Summary

Alcohol intake may slow fat burning. While excessive drinking may increase your body fat percentage, light to moderate drinking does not show the same effects.

Many people undertake intermittent fasting to lose weight.

Alcohol is calorie-dense, with just 1 gram proving 7 calories. Only 1 drink can contribute 100 or more calories to your daily intake (7).

That said, research is mixed on whether alcohol intake promotes weight gain (5, 7).

In fact, several observational studies show that moderate drinking could reduce your risk of weight gain (5, 8, 9).

However, heavy drinking — defined as 4 or more drinks per day for men and 3 or more per day for women — is linked to an increased risk of weight gain and obesity (5, 9, 10).

Summary

Although alcohol is calorie-dense, moderate intake may reduce your risk of weight gain. On the other hand, excessive drinking may increase your risk.

Intermittent fasting has been shown to reduce inflammation in your body.

Nonetheless, alcohol may promote inflammation, counteracting the effects of this diet (1).

Chronic inflammation may promote various illnesses, such as heart disease, type 2 diabetes, and certain cancers (11).

Research shows that the inflammation from excessive drinking may lead to leaky gut syndrome, bacterial overgrowth, and an imbalance in gut bacteria (12, 13, 14).

High alcohol intake can also overwhelm your liver, decreasing its ability to filter out potentially harmful toxins (14, 15).

Together, these effects on your gut and liver may promote inflammation throughout your body, which over time can lead to organ damage (15).

Summary

Excessive alcohol intake can cause widespread inflammation in your body, counteracting the effects of intermittent fasting and potentially leading to diseases.

During a fast, you’re supposed to avoid all foods and beverages for a set amount of time.

Specifically, intermittent fasting is meant to promote hormonal and chemical changes — such as fat burning and cellular repair — that may benefit your health.

As alcohol contains calories, any amount of it during a fasting period will break your fast.

All the same, it is perfectly acceptable to drink in moderation during your eating periods.

Alcohol may prevent cellular repair

During fasting periods, your body initiates cellular repair processes like autophagy, in which old, damaged proteins are removed from cells to generate newer, healthier cells (16).

This process may reduce your risk of cancer, promote anti-aging effects, and at least partly explain why calorie restriction has been shown to increase lifespan (16, 17).

Recent animal studies demonstrate that chronic alcohol intake may inhibit autophagy in liver and fat tissue. Keep in mind that human studies are needed (18, 19).

Summary

As alcohol contains calories, drinking any amount during a fasting period will break your fast and may prevent cellular repair processes.

As alcohol breaks your fast if consumed during a fasting period, it’s recommended to only drink during your designated eating periods (20).

You should also keep your intake in check. Moderate alcohol consumption is defined as no more than 1 drink per day for women and no more than 2 per day for men (21).

While intermittent fasting doesn’t have strict rules for food and beverage intake, some alcohol choices are healthier than others and less likely to counteract your dietary regimen.

Healthier options include dry wine and hard spirits, as they’re lower in calories. You can sip these on their own or mixed with soda water.

To limit your sugar and calorie intake, avoid mixed drinks and sweeter wines.

Summary

During intermittent fasting, it’s best to drink alcohol in moderate amounts and only during your eating periods. Healthier options include dry wine and hard spirits.

If consumed in moderation and only during eating periods, alcohol is unlikely to impede intermittent fasting.

Still, it’s calorie-dense and may slow fat burning. Excess drinking may promote chronic inflammation and other health issues.

To cut back on excess calories and sugar, choose dry wine or hard spirits rather than mixed drinks.