The 16:8 Method of Intermittent Fasting

The 16:8 method means eating all of your food within an 8-hour window each day and fasting for the other 16 hours, for example eating between 12pm and 8pm. During the fast you drink water, black coffee, or plain tea. Much of the fast happens overnight while you sleep, which is why 16:8 is one of the most popular ways to start intermittent fasting.

This page covers how 16:8 works, sample schedules, how to start gradually, what to eat, common challenges, and what research does and does not show. If 16:8 feels easy after a few weeks, some people move on to 18:6 fasting.

What is the 16:8 Method?

The 16:8 method of intermittent fasting involves restricting your daily eating period to 8 hours and fasting for the remaining 16 hours. During the fasting period, you consume no calories, although water, black coffee, and other non-caloric beverages are allowed.

For example, if you choose to eat between 12 PM and 8 PM, you would fast from 8 PM until 12 PM the next day. This creates a daily 16-hour fasting period and an 8-hour eating window.

Key Features of 16:8 Fasting

  • Daily 16-hour fasting period
  • 8-hour eating window
  • Can be practiced every day or several days per week
  • No calorie counting required (though food quality still matters)
  • Flexible scheduling to fit your lifestyle

16:8 is popular because it is simple and fairly easy to fit around daily life. The 8-hour window usually allows two or three meals and fits most family and social meal times, while the fast mostly overlaps with sleep.

Who Should Check with a Doctor First

16:8 is not recommended without medical advice if you are pregnant or breastfeeding, under 18, underweight, have a history of eating disorders, have diabetes (especially if you take insulin or sulfonylureas), or take medication that must be taken with food. See fasting safety.

Key Benefits of the 16:8 Method

Simplicity and Sustainability

The 16:8 method is straightforward to understand and implement. Unlike more complex diets, you simply restrict the timing of your meals rather than constantly tracking specific foods or macronutrients.

Fewer Late-Night Snacks

A fixed eating window naturally cuts out late-evening snacking, which is often a source of extra calories. Many people end up eating somewhat less overall without counting calories.

Reduced Meal Planning

With fewer meals to prepare each day, many find that the 16:8 method simplifies their daily routine and reduces the time spent on meal preparation and cleanup.

Possible Metabolic Effects

Some research suggests time-restricted eating may modestly improve measures such as insulin sensitivity in some people, often alongside weight loss. Results are mixed, and many people notice no change in how they feel.

More Awareness of Eating Habits

Some people find that having set eating times makes them more aware of when and why they eat. Others find strict timing stressful; if that happens, a more relaxed approach may suit you better.

Important Note: This website focuses on the lifestyle aspects of fasting rather than specific health claims. While research on intermittent fasting is promising, individual results vary. Always consult with healthcare providers before beginning any fasting regimen.

How to Implement the 16:8 Method

Starting with the 16:8 fasting method is relatively straightforward, but a gradual approach often leads to better long-term success. Here's a step-by-step implementation plan:

1

Start Gradually

If you're new to fasting, begin with a 12-hour fast and gradually extend it. For example, finish dinner at 8 PM and have breakfast at 8 AM the next day, then slowly push breakfast later until you reach your desired 16-hour fasting window.

2

Choose Your Window

Select an 8-hour eating window that aligns with your schedule and preferences. Common windows include 12pm to 8pm (skipping breakfast) or 10am to 6pm (early dinner).

3

Stay Hydrated

During fasting periods, consume plenty of water. Black coffee, plain tea, and other non-caloric beverages are also generally acceptable and can help manage hunger.

4

Focus on Nutrition

Within your eating window, prioritize nutrient-dense whole foods. Just because you're fasting doesn't mean nutrition isn't important during eating periods.

5

Be Consistent

Try to keep similar eating times each day. A regular routine usually makes hunger more predictable.

6

Track Your Experience

Keep a journal of how you feel during fasting periods and after breaking your fast. This can help you identify patterns and make adjustments as needed.

Finding Your Ideal Schedule

One of the major advantages of the 16:8 method is its flexibility. Your ideal schedule should align with your natural hunger patterns, work schedule, social obligations, and lifestyle preferences.

Common 16:8 Schedules

Early Bird Schedule

Eating window: 8 AM to 4 PM

Suits early risers who like breakfast and are happy with an early dinner. Some research suggests earlier eating windows may be better for blood sugar control, although the evidence is still limited.

Classic Schedule

Eating window: 12 PM to 8 PM

Probably the most common schedule: you skip breakfast and eat lunch and dinner. Works well if you are not hungry in the morning and like having dinner with family or friends.

Late Schedule

Eating window: 2 PM to 10 PM

Suits night owls or people with evening commitments. Eating late can affect sleep or cause reflux for some people, so try to finish 2-3 hours before bed.

Tip: Be Flexible

While consistency is important, don't be afraid to adjust your window for special occasions or weekends. The occasional adjustment won't derail your overall practice.

What to Eat During Your Window

While the 16:8 method focuses on when you eat rather than what you eat, the quality of your food still matters for your health and for how you feel during the fast.

Nutrient-Dense Foods to Prioritize

Proteins

Include quality protein sources at each meal to support satiety and muscle maintenance:

  • Lean meats and poultry
  • Fish and seafood
  • Eggs
  • Legumes and beans
  • Tofu and tempeh
  • Greek yogurt

Complex Carbohydrates

Choose fiber-rich, slow-digesting carbohydrates:

  • Whole grains (oats, quinoa, brown rice)
  • Sweet potatoes and other starchy vegetables
  • Fruits
  • Legumes

Healthy Fats

Include sources of beneficial fats:

  • Avocados
  • Olive oil
  • Nuts and seeds
  • Fatty fish

Vegetables

Aim for a variety of colorful vegetables:

  • Leafy greens
  • Cruciferous vegetables
  • Bell peppers
  • Tomatoes
  • Carrots

Breaking Your Fast

How you break your fast can impact how you feel throughout your eating window. Consider these approaches:

  • Start moderately: Begin with a balanced meal rather than a very large meal, which can cause discomfort after fasting.
  • Balanced composition: Include protein, vegetables, healthy fats, and fiber-rich carbohydrates to help you stay full.
  • Hydration: Include hydrating foods like fruits and vegetables or have water with your meal.

Some people find that a smaller meal to break the fast followed by a larger meal later works best, while others prefer to eat two substantial meals during their window. Experiment to find what works for you. For more ideas, see how to break a fast and fasting meal plans.

Frequently Asked Questions

Can I drink water during fasting?

Yes, staying hydrated during your fasting window is important. Water, black coffee, plain tea, and other non-caloric beverages are generally acceptable during fasting.

Do I need to follow 16:8 every day?

While consistency helps your body adapt, many people follow 16:8 on 5-6 days a week and allow more flexibility on weekends or special occasions.

Will I lose muscle on the 16:8 diet?

When implemented properly with adequate protein intake during your eating window and regular strength training, 16:8 is unlikely to cause significant muscle loss for most people. Studies combining time-restricted eating with resistance training suggest muscle can be maintained when protein intake is adequate.

Can I take supplements while fasting?

Fat-soluble vitamins and supplements that contain calories are best taken during your eating window. Water-soluble vitamins and minerals can be taken during the fasting period if needed, though they may be better absorbed with food.

How long does it take to adapt to 16:8 fasting?

It varies. Many people find the first week or two the hardest and then settle into the routine, but some take longer. Starting with a shorter fast and building up gradually usually helps.

Can I exercise while fasting?

Yes, many people exercise while fasted. Light to moderate activity is generally well-tolerated. For intense workouts, you may prefer scheduling them within your eating window, especially when first adapting to the fasting schedule.

Tips for Success

Stay Busy During Fasting Hours

Engaging in activities that keep your mind occupied can help manage hunger, especially when first adapting to the fasting schedule.

Practice Mindful Eating

During your eating window, eat mindfully without distractions. This can enhance satisfaction from meals and improve digestion.

Prioritize Sleep

Poor sleep can increase hunger and make fasting more difficult. Aim for 7-9 hours of quality sleep to support your fasting practice.

Use a Timer

A fasting timer can help you track your fasting periods and build a routine. You can use the free fasting timer on our homepage.

Look Beyond the Scale

Pay attention to how you feel, how you sleep, and how your clothes fit, not just the number on the scale.

Get Support

Having a friend or family member who understands your eating schedule can make it easier to stick with.

Common Challenges and Solutions

Morning Hunger

Challenge: Feeling excessively hungry in the morning, especially if you're used to eating breakfast.

Solutions:

  • Stay hydrated with water, black coffee, or tea
  • Gradually extend your fasting window over several weeks
  • Consider an earlier window that includes breakfast (for example 8am-4pm) if morning hunger persists

Social Situations

Challenge: Navigating meals with friends or family that fall outside your eating window.

Solutions:

  • Adjust your eating window occasionally for special events
  • Suggest meeting times that align with your eating window
  • Participate socially without eating, focusing on the company rather than the food

Energy Fluctuations

Challenge: Experiencing energy dips, especially during the adaptation phase.

Solutions:

  • Ensure you're eating enough during your eating window
  • Focus on balanced nutrition with adequate protein, healthy fats, and complex carbohydrates
  • Adjust the timing of your eating window to better align with your energy needs

Overeating During the Window

Challenge: Consuming excessive calories during your eating window due to increased hunger.

Solutions:

  • Plan your meals ahead of time
  • Start your eating window with a balanced, satiating meal
  • Eat mindfully, taking time to enjoy your food
  • Include plenty of protein and fiber-rich foods

Scientific Research on 16:8 Fasting

Time-restricted eating, including 16:8, has been studied in a number of small, mostly short-term trials. Overall, they suggest that it can help some people eat less and lose a modest amount of weight. Larger trials that compare time-restricted eating with ordinary calorie restriction at the same calorie level have generally found similar results, which suggests that the main effect comes from eating less. A few examples:

An 8-Hour Eating Window in Adults with Obesity

In this small 12-week pilot study, adults with obesity ate only between 10am and 6pm. They ate fewer calories and lost a small amount of weight compared with a historical control group. Because it was small and not randomized, it cannot show cause and effect.

Effects of 8-hour time restricted feeding on body weight and metabolic disease risk factors in obese adults: A pilot study. Nutrition and Healthy Aging (2018).

Time-Restricted Feeding and Resistance Training

In this randomized trial, active women followed an 8-hour eating window while doing resistance training. With adequate protein intake, they maintained or gained lean mass and strength similarly to women on a normal eating schedule.

Time-restricted feeding plus resistance training in active females: a randomized trial. American Journal of Clinical Nutrition (2019).

Circadian Rhythm and Meal Timing

This small, tightly controlled study in men with prediabetes used an early 6-hour eating window (ending mid-afternoon) rather than 16:8. It found improvements in insulin sensitivity and blood pressure even without weight loss. It suggests meal timing may matter, but the study was very small and short, and it has not shown that 16:8 at other times of day has the same effect.

Early Time-Restricted Feeding Improves Insulin Sensitivity, Blood Pressure, and Oxidative Stress Even without Weight Loss in Men with Prediabetes. Cell Metabolism (2018).

Important Note: The research on intermittent fasting is still evolving. Individual responses vary, and more long-term studies are needed. This information is provided for educational purposes and should not be considered medical advice. Always consult healthcare providers before beginning any fasting regimen.

The 16:8 Method: A Sustainable Approach to Fasting

The 16:8 method offers a balanced, flexible approach to intermittent fasting that can be adapted to various lifestyles. Its simple structure makes it a common starting point for beginners. Research suggests modest benefits for some people, mainly through eating less, and it is not the right choice for everyone.

As with any lifestyle change, success often comes from consistency, patience, and making adjustments based on your individual needs and experiences. Remember that fasting is a practice, not a binary success or failure, and finding what works for your body and life circumstances is key.

If you have a medical condition or take regular medication, talk to your healthcare provider before starting.

Ready to Try 16:8?

Use our free fasting timer to track your fasting and eating windows.