The trends of eating while standing, sitting and lying down have all had their moments in the spotlight.

For instance, eating while lying down was particularly fashionable in ancient Rome and Greece. Since then, sitting down to eat has become the most encouraged posture.

More recently, some people have started standing while eating, either as a way to save time or counter a sedentary office job. However, others insist that standing while eating may be harmful to digestion and lead to overeating.

This article investigates the effects of eating while standing up and whether it is harmful.

The posture you adopt while eating can influence your ability to digest food.

That's because food empties from the stomach more slowly when a person is sitting or lying down, compared to when they are standing. The exact reasons why are not fully known, but gravity seems to play a role (1, 2).

One study compared the digestion speeds of women who either sat or laid down immediately after a meal. The women who laid down took around 22 additional minutes to digest their food, compared to those who sat (1).

Another study compared digestion speeds in individuals who laid down, sat, stood or moved around after a sit-down meal.

Those who laid down after eating took 54–102% longer to digest their food, compared to the other three groups. On the other hand, those who stood up and moved around digested their food the quickest.

The researchers also directly compared the effects of standing and sitting after a meal. Those who stood digested their food slightly faster. However, the five-minute difference was too small to be considered significant (2).

No studies comparing the digestion speeds of people who sat or stood while they were eating could be found.

However, the sit-down meals in the above studies were often consumed very quickly, so similar food digestion times could be expected for standing.

Summary: Your posture can affect how quickly you digest food. Digestion is slowest when you’re lying down and quickest when you’re standing up and moving. However, there seems to be little difference between sitting and standing immediately after a meal.

Some people believe that standing while eating can help you lose more weight than sitting while eating. However, the opposite may be true.

Even though standing up may burn around 50 more calories per hour than sitting, this is not necessarily enough to make a difference over time.

That's because most people consume their meals relatively quickly. So in the best-case scenario, consuming a meal standing up may help you burn about 12–25 extra calories.

In contrast, sitting down for a meal is more likely to reduce the speed at which you eat, potentially reducing the number of calories you consume to an even greater extent.

Several studies show that eating more slowly can reduce appetite and increase feelings of fullness, both of which may reduce the total number of calories consumed during a meal. This may result in up to 88 fewer calories eaten per meal (3, 4, 5).

Sitting down for a meal may also help your brain register that you've consumed a "real meal," reducing the likelihood you'll overeat during the following meal (6).

Summary: Eating while standing up may increase the speed at which you eat, which could cause you to overeat and consume more calories. The few extra calories you’ll burn while standing probably won’t be enough to compensate.

Your body has several different ways to determine whether you’re hungry or full.

One of them is sensing how much food is present in the stomach. The degree to which your stomach stretches after a meal can let your brain know whether you have eaten enough (7).

The more your stomach stretches and the longer it remains full, the less hungry you’re likely to feel. That's why foods that are digested quickly, such as processed carbs, tend to leave you feeling hungrier than those that take longer to digest, such as fiber and protein (8, 9).

Although there isn't much difference in the speed of digestion between eating while sitting or standing, the difference does become significant when you factor in movement.

Moving around immediately after eating causes your stomach to empty and your gut to digest foods up to 30% faster (2).

Research has linked quicker stomach emptying to increased feelings of hunger after a meal. Thus, those who stand up and walk while eating may feel hungrier after a meal than those who simply stand still or sit down (10).

Summary: Eating while standing up may not cause you to feel hungrier. However, eating while standing and moving around may lead you to feel hungrier after a meal than you would have felt otherwise.

Gastric reflux happens when the contents of the stomach come back up into the esophagus. This can lead to a burning feeling in the middle of the chest, commonly recognized as heartburn.

Those with reflux are often advised to stand upright and avoid reclining or slouching while eating, as well as for several hours after a meal (11, 12).

That's because reclining or slouching increases pressure in the stomach, making it more likely that food will be pushed back up into the esophagus.

Reflux is also more likely to happen when there’s too much food in the stomach. This puts pressure on the valve that separates the esophagus from the stomach, increasing the likelihood that the contents of the stomach will travel back up (13).

Interestingly, eating while sitting upright or standing up can reduce pressure in the stomach, reducing the likelihood of reflux.

Moreover, eating while standing and moving around, such as during a walking meal, may help food exit the stomach more quickly, further lowering the likelihood of reflux and heartburn (2).

Summary: Individuals with reflux or heartburn may benefit from standing upright while eating. Moreover, standing up and walking during a meal may speed digestion, further reducing the likelihood of reflux and heartburn.

In some cases, eating while standing may prevent proper digestion.

That's partly because eating while standing may cause some people to eat more quickly. This could increase the amount of air swallowed during a meal, potentially worsening gas and bloating (14).

What's more, the more upright your body position, the quicker your digestion (2).

A faster digestion can be problematic because it allows less time for nutrients to come into contact with the gut wall, making it more difficult for your body to absorb them (1, 15).

When carbs are poorly digested, they tend to ferment in the gut, causing gas and bloating.

Anyone can experience gas and bloating from undigested carbs. However, two groups of people are particularly likely to experience such discomforts — those who are lactose intolerant or sensitive to FODMAPs. FODMAPs are a group of foods that can cause gas (16).

People who eat their meals quickly or walk around during or immediately after eating may digest their meals up to 30% faster. This may increase the likelihood of poor carb digestion, gas and bloating.

Summary: Eating while standing up may increase gas and bloating by affecting eating speed and nutrient absorption.

Mindfulness should be an important part of every meal.

Research shows that practicing mindfulness during meals can help you experience more pleasure while eating and reduce the likelihood of overeating (17).

Mindful eating requires you to focus all your senses on the experience of eating. This goes hand-in-hand with eating more slowly and taking the time to enjoy your meal.

Standing up doesn't necessarily mean you cannot exercise mindfulness while eating. However, eating quickly while standing up at the counter between meetings can make mindful eating more challenging.

If you find this tends to be the type of eating you do while standing, it may be better to sit down and enjoy your meal slowly, away from your phone, computer, TV and other distractions.

Summary: Standing up while eating may make it more difficult to practice mindful eating. Instead, try sitting down, distancing yourself from distractions and focusing all your senses on the meal.

Eating while standing may make you more prone to overeating, becoming hungrier faster or feeling bloated and gassy.

However, there's little evidence to support the notion that eating while standing up is harmful. In fact, eating while standing up may be beneficial for reducing reflux and heartburn.

That's not to say that eating while standing is necessarily more beneficial than eating in a proper sitting position.

As long as you can slow down and eat mindfully, whether you eat sitting or standing appears to matter very little.