How Diet, Stress and Sleep Shape Liver Health

The liver is one of the most vital organs in the body, yet it is often overlooked until something goes wrong. According to Saima Ajaz, M.B.B.S., Ph.D., a hepatology and lifestyle medicine physician at King’s College Hospital, protecting liver health starts with understanding just how much our everyday choices affect it.

The liver carries out more than 500 essential functions, including processing fats, sugars, proteins and cholesterol, as well as helping regulate metabolism and energy use. Because of this central role, nearly everything we do (what we eat, how much we move, how we sleep and how we manage stress) directly influences liver health. When these lifestyle factors are out of balance, the liver can become damaged, making it harder for the body to function properly.

One of the biggest concerns today is fatty liver disease, which affects roughly one in three people in the U.K. and is increasingly common worldwide. This condition is closely linked to obesity, excess visceral fat and diets high in processed foods and added sugars. The liver is a major fat-storage organ, so when the body is overloaded with unhealthy calories, the liver often bears the burden.

Ajaz emphasizes that the most effective ways to protect the liver are also some of the simplest. Eating a healthy, balanced diet with fewer processed foods and less added sugar is key. Maintaining a healthy weight, staying physically active, getting enough sleep and managing stress all play important roles in supporting liver function. These habits are especially critical for people who already have a liver condition.

Alcohol is another major factor. Drinking within recommended limits may not harm the liver, but consistently exceeding those limits can lead to significant damage over time. In addition, overuse of medications, such as frequent use of painkillers without medical guidance, can place extra strain on the liver, which is responsible for processing many drugs and toxins.

Gut health also plays a growing role in liver health. Emerging research shows strong links between the gut and the liver, highlighting the importance of eating fiber-rich foods, fruits, vegetables and fermented foods and staying well hydrated.

Ultimately, the liver is essential to long-term metabolic health. It contains a high number of mitochondria (the energy-producing structures in cells) because it requires so much energy to perform its many tasks. When the liver is damaged, those processes begin to fail. Protecting liver health through everyday lifestyle choices is one of the most powerful ways to support overall health and prevent future disease.