There are mixed opinions about snacking.
Some believe that it is healthy, while others think it can harm you and make you gain weight.
Here is a detailed look at snacking and how it affects your health.
Snacking is when you consume food or beverages between your regular meals.
The term "snack foods" is often used to refer to processed, high-calorie foods like chips and cookies.
However, "snacking" simply means to eat or drink something between meals, regardless of whether the food is healthy or not (1).
Hunger is the main motivation behind snacking, but factors like location, social environment, time of day and food availability contribute as well.
In fact, people often snack when there is appetizing food around, even if they're not hungry.
In one study, when overweight and obese people were asked why they chose unhealthy snacks, the most common response was temptation, followed by being hungry and feeling low on energy (2).
In addition, both the desire to snack and snacking's effects on health appear to be highly individualized. Factors that influence snacking include age and beliefs about whether snacking is healthy or not (3).
Bottom Line: Snacking refers to eating or drinking outside of regular meals. Reasons for snacking include hunger, food availability and environmental and social cues.
Although it's been suggested that eating every few hours will increase your metabolism, the evidence does not support this.
Studies have found that meal frequency has no significant effect on how many calories you burn (4).
In one study, researchers compared the responses of people who consumed an equal number of calories in either two or seven meals per day. They found no difference in calories burned (5).
In another study, obese people who followed a very low-calorie diet for three weeks showed similar decreases in metabolic rate, regardless of whether they ate 800 calories as one or five meals per day (6).
Interestingly, one study reported that a bedtime snack may lead to a higher metabolic rate the next morning.
In this study, when active young men consumed a high-protein or high-carb snack before bed, they experienced a significant increase in metabolic rate the following morning (7).
However, this increase in metabolism would be expected, given that the snacks provided additional calories that were burned overnight. The researchers didn't compare the effect of including these foods at meals instead.
Bottom Line: Snacking every few hours is often believed to increase metabolism. However, studies have shown that eating frequency has little or no effect on metabolism.
Studies on snacking's effects on appetite and weight have provided mixed results.
Snacking's Effects on Appetite
How snacking affects appetite and food intake isn't universally agreed upon.
One review reported that although snacks may briefly satisfy hunger and promote feelings of fullness, their calories aren't compensated for at the next meal.
This results in increased calorie intake for the day (8).
For example, in one study, overweight men who ate a 200-calorie snack two hours after breakfast ended up eating only 100 fewer calories at lunch (9).
This means that total calorie intake increased by about 100 calories.
In another controlled study, lean men ate either three high-protein, high-fat or high-carb snacks for six days (10).
Their hunger levels and total calorie intakes didn't change compared to the days on which they ate no snacks, indicating that the snacks had a neutral effect (10).
In one study, when men ate a high-protein, high-fiber snack bar, they had lower levels of the hunger hormone ghrelin and higher levels of the fullness hormone GLP-1. They also took in an average of 425 fewer calories per day (12).
Another study in 44 overweight or obese women found that a bedtime snack high in protein or carbs led to decreased hunger and greater feelings of fullness the next morning. However, insulin levels were also higher (13).
Based on these varied results, it appears that snacking's effect on appetite may depend on the individual and type of snack consumed.
Snacking's Effects on Weight
For example, a non-controlled study in 17 people with diabetes reported that consuming snacks high in protein and slow-digesting carbs resulted in an average weight loss of 2.2 pounds (1 kg) within four weeks (17).
In one study, 36 lean men increased their calorie intake by 40% by consuming excess calories as snacks between meals. They experienced a significant increase in liver fat and belly fat (19).
Interestingly, another controlled study suggests that the timing of snacks may be what makes a difference when it comes to weight changes.
This study in 11 lean women found that consuming a 190-calorie snack at 11:00 p.m. reduced the amount of fat they burned significantly more than consuming the same snack at 10:00 a.m. (20).
The mixed results suggest that weight responses to snacking probably vary by individual.
Bottom Line: Mixed results from several studies suggest that weight and appetite responses to snacking vary by individual.
Although many people believe that it's necessary to eat frequently to maintain stable blood sugar levels throughout the day, this isn't always the case.
In fact, a 2014 study in people with type 2 diabetes found that eating only two large meals per day resulted in lower fasting blood sugar levels, better insulin sensitivity and greater weight loss than eating six times per day (21).
Of course, the type of snack and amount consumed are the main factors that affect blood sugar levels.
Lower-carb, higher-fiber snacks have consistently been shown to have a more favorable effect on blood sugar and insulin levels than high-carb snacks in people with and without diabetes (12, 22, 23, 24).
Bottom Line: It isn't necessary to snack to maintain healthy blood sugar levels. Eating high-protein or high-fiber snacks raises blood sugar levels less than consuming high-carb snacks.
Snacking may not be good for everyone.
However, it can definitely help some people avoid becoming ravenously hungry.
When you go too long without eating, you may become so hungry that you end up eating many more calories than you need.
Snacking can help keep your hunger levels on an even keel, especially on days when your meals are spaced further apart.
However, it's important to make healthy snack choices.
Bottom Line: Eating a snack is better than letting yourself become ravenously hungry. This can lead to poor food choices and eating more calories than you need.
In order to get the most out of your snacks, follow these guidelines:
- Amount to eat: In general, it's best to eat snacks that contain about 200 calories and at least 10 grams of protein to help you stay full until your next meal.
- Frequency: The number of snacks you need will vary based on your activity level and how big your meals are. If you're very active, you may prefer 2–3 snacks per day, while a more sedentary person may do best with one snack or no snacks.
- Portability: Keep portable snacks with you when you're out doing errands or traveling in case hunger strikes.
- Snacks to avoid: Processed, high-sugar snacks may give you a brief jolt of energy, but you'll probably feel hungrier an hour or two later.
Bottom Line: When snacking, be sure to eat the right types and amounts of food in order to reduce hunger and prevent overeating later on.
Although there are many packaged snacks and bars on the market, choosing nourishing real food is best.
It's a good idea to include a protein source in your snack.
Here are a few other healthy snack ideas:
- String cheese
- Fresh vegetable slices
- Sunflower seeds
- Cottage cheese with fruit
Also, check out this list of 29 healthy snacks.
Bottom Line: Choosing healthy snacks that are high in protein and fiber helps reduce hunger and keeps you full for several hours.
Snacking can be good in some cases, such as for preventing hunger in people who tend to overeat when going too long without food.
However, others may do better eating three or fewer meals per day.
In the end, it's really a personal choice. If you're going to snack, make sure to choose healthy foods that keep you full and satisfied.