Intermittent fasting, a dietary approach that cycles between periods of fasting and eating, has become a popular way to lose weight and improve metabolic health. One common intermittent fasting protocol is limiting food intake to two meals per day, with fasting periods in between. But is condensing your eating into just two meals per day healthy? Here is a look at the evidence behind this practice.
What is intermittent fasting?
Intermittent fasting (IF) is an eating pattern that involves cycling between periods of eating and fasting. It does not specify which foods to eat, but when to eat them. The most common IF protocols include:
- 16/8 method: Fast for 16 hours per day and restrict eating to an 8-hour window.
- 5:2 diet: Eat normally 5 days per week and restrict calories to 500–600 per day for 2 days.
- Eat-stop-eat: Fast for 24 hours 1–2 times per week.
- Alternate day fasting: Fast every other day.
Two meals per day fits best with the 16/8 method of intermittent fasting, where you confine all eating to an 8-hour window. For example, you might eat your first meal at 12pm and last meal at 8pm. The 16–18 hours in between meals is the fasting period. This fasting/feeding cycle is often repeated daily.
Benefits of intermittent fasting
Here are some of the most common benefits associated with intermittent fasting when followed on a consistent basis:
- Weight loss: By limiting the number of hours for eating, you reduce calorie intake. This can lead to steady weight loss over time.
- Reduced inflammation: Some studies show reductions in markers of inflammation during intermittent fasting.
- Improved insulin sensitivity: Fasting periods allow insulin levels to lower, which can improve insulin resistance.
- Better cardiovascular health: Some studies show intermittent fasting may reduce blood pressure, LDL cholesterol and triglycerides.
- Increased longevity: Animal studies link intermittent fasting methods like alternate day fasting to longer lifespan.
However, human studies show these benefits are most pronounced when intermittent fasting is combined with lifestyle modifications like eating healthy and exercising.
Potential downsides of intermittent fasting
Intermittent fasting may have potential downsides as well, including:
- Hunger: Fasting periods can increase hunger and food cravings for some people.
- Suboptimal nutrition: IF makes it harder to meet all your nutritional needs if eating fewer meals.
- Low energy: Difficulty with fasting may lead to low energy, headaches or lack of focus during workouts.
- Binge eating: Some research indicates fasting periods may promote subsequent binge eating in vulnerable individuals.
- Dehydration: Extended periods without fluids can cause dehydration.
Whether intermittent fasting causes these side effects seems to vary by individual. People at risk for disordered eating may want to avoid fasting protocols.
Is two meals a day healthy?
Eating just two meals per day every day is one form of intermittent fasting. Here is a closer look at the potential upsides and downsides of this eating pattern.
Potential benefits of two meals per day
- Weight loss: Condensing your food intake into two meals makes it easier to cut calories and lose weight over time.
- Reduced insulin resistance: Studies show insulin sensitivity improves after meals. So having two larger meals with a robust fasting period in between may improve insulin function.
- Lower cholesterol: Some research indicates just one large meal per day may lower LDL cholesterol compared to three meals with the same calories.
- Longer lifespan: Animal studies link meal timing to longevity. Mice fed one large daily meal lived longer than those fed multiple smaller meals.
However, current evidence has not confirmed that two meals per day is better than three for weight loss or metabolic disease prevention in humans.
Potential downsides of two meals per day
- Nutrient deficiencies: Condensing your food intake into just two meals makes it harder to meet all your nutritional needs for vitamins, minerals, fiber and protein.
- Suboptimal protein intake: Spreading protein intake evenly throughout the day helps stimulate muscle protein synthesis. Two meals may reduce muscle mass gains compared to three.
- Hunger: Some people experience increased hunger and food cravings when restricting intake to two meals.
- Low blood sugar: Going too long between meals may result in drops in blood sugar, which can cause fatigue, headaches, irritability and poor concentration.
- Disordered eating risk: For those predisposed to eating disorders, significant calorie restriction may trigger binge eating after the fasting period.
Who should avoid two meals a day?
While intermittent fasting like two meals a day may suit some people, it is not recommended for everyone. The following groups should generally avoid restricting intake to just two meals daily:
- Children and teenagers
- Women who are pregnant or breastfeeding
- People with a history of disordered eating
- Those with medical conditions like diabetes or low blood sugar
- Active individuals and athletes with high calorie needs
- Older adults who often have increased nutrient needs
For those who do choose to follow this eating pattern, working with a registered dietitian can help ensure nutritional needs are met within two meals.
Tips for following two meals per day
If you want to try condensing your food intake into two meals daily, here are some tips to do so safely and effectively:
- Choose nutritious foods. Focus on high protein foods like meat, fish, eggs and plant proteins. Get plenty of fruits and vegetables. Choose whole grains over refined.
- Don’t skimp on calories. Cutting intake too low can backfire and cause intense hunger. Determine your calorie needs for weight loss and stick to that target.
- Time meals right. Having two bigger meals works best by finishing your last meal 3-4 hours before bedtime.
- Stay hydrated. Drink water and calorie-free beverages during fasting periods.
- Listen to hunger cues. Increase meal size or frequency if you feel weak, fatigued or ravenously hungry.
- Exercise smart. Save intense workouts for after meals, not during fasting periods.
- Get enough protein. Shoot for 25-30 grams of protein per meal to support muscle mass.
Sample meal plans
Here are two sample meal plans with about 1400 calories each for one day of two meals a day:
Meal plan #1
Meal 1 (12pm):
- 3 eggs scrambled with 1 cup spinach, 1 oz feta cheese
- 1 slice whole grain toast
- 1/2 grapefruit
Meal 2 (6pm):
- 4 oz grilled salmon
- 1 cup quinoa
- 1 cup roasted Brussels sprouts
- 1 cup blueberries
Meal plan #2
Meal 1 (2pm):
- Tuna salad sandwich on whole grain bread
- Carrot sticks
- Seltzer water
Meal 2 (8pm):
- 1 cup vegetarian chili
- Side salad with vinaigrette
- 1 oz dark chocolate
The bottom line
Eating two meals per day is one approach to intermittent fasting. Condensing your food intake into two bigger meals separated by 16-18 hours of fasting may help some people lose weight and improve metabolic health. However, it can be difficult to meet all nutritional needs this way. Two meals a day may work well for some but should be avoided by teenagers, pregnant women, diabetics and those at risk of eating disorders. Overall, more quality research is needed on this eating pattern in humans.
