Cologne, Germany - It's tempting to eat heartily in the bitter cold of winter and the holidays seem like a perfect time to knock back a few drinks. But regular consumption of excess calories and more damaging substances than the liver can process can mean damage, like fatty liver.

"We think that, here in Germany, about every fourth adult is affected by this form of liver disease," says Richard Raedsch of St Josef's Hospital in Wiesbaden.

The illness occurs when large amounts of triglycerides accumulate in the liver cells. The way the fat is stored makes a difference. If a third of liver cells are storing fat, then it is a mild case of fatty liver. Once two-thirds of the cells are affected, it is considered an advanced case. If more than two-thirds of cells are affected, it is a severe case.

It is all too easy to overlook initial warning signs. At first, the liver is enlarged, but works normally. "The symptoms are very nonspecific: exhaustion, drowsiness or slight pressure in the right upper abdomen are all part of it," says Claus Niederau of the German Liver Assistance Organization.

In about 10 per cent of all cases, the fatty liver, or steatosis hepatitis, turns into a fatty liver inflammation, or steatohepatitis. "The inflammation comes about because the liver cells try to ward off the accumulation," explains Raedsch.

The inflammation can be recognized by flu-like symptoms or pain beneath the right ribs. Eventually, just as in viral hepatitis, people will develop a yellowish colour in their skin and corneas. The infection also diminishes production of gall, which leads to discolouration of the stool. Urine will darken in colour.

A chronic inflammation can lead to the serious danger that the liver tissue that dies will be replaced by connective tissue. "This scarring usually manifests itself as irreversible liver cirrhosis and increases the risk of liver cancer," warns Mathias Plauth, chief physician at the Dessau Clinic for Internal Medicine and an expert on liver disease with the German Association for Nutritional Medicine.

Such irreversible liver damage can be avoided if the fatty deposits are noticed early. Standard treatment involves stopping the accumulation of fat.

"The main causes are being overweight and excessive alcohol consumption, usually in combination," says Niederau. Certain metabolic diseases, like diabetes mellitus, or medications can lead to the fat buildup.

"That means the lifestyle has to change and the patient has to cut back on alcohol and calorie-rich food, especially fatty food, while increasing calories burned with exercise," he advises. In an ideal situation, the tissue affected by the fatty liver or fatty liver hepatitis can recover on its own with such measures. (dpa)