Your liver is the largest organ inside your body. It helps you digest food, store energy, and remove harmful substances (toxins). Steatotic liver disease, formerly called fatty liver disease, happens when too much fat builds up in your liver. It's typical to have some fat in your liver cells, but too much can be a problem.

There are two main types of steatotic liver disease:

• Metabolic dysfunction-associated steatotic liver disease (MASLD)
• Alcohol-associated liver disease (ALD)

MASLD is a type of steatotic liver disease that is not caused by heavy alcohol use. It used to be called nonalcoholic fatty liver disease. There are two main forms:

• Simple fatty liver, in which you have fat in your liver but little or no inflammation or liver damage. This form usually does not get bad enough to cause liver damage or complications.
• Metabolic dysfunction-associated steatohepatitis, or MASH (previously called nonalcoholic steatohepatitis or NASH), is when MASLD gets worse. In addition to fat in your liver, MASH may cause inflammation and liver damage. This can lead to fibrosis, or scarring, of the liver. This scarring sometimes leads to cirrhosis or liver cancer.

ALD is caused by heavy alcohol use. It used to be called alcoholic fatty liver disease, or alcoholic steatohepatitis.

Your liver breaks down most of the alcohol you drink, so it can be removed from your body. But the process of breaking it down can create harmful substances. These substances can damage liver cells, cause inflammation, and weaken your body's natural defenses. The more alcohol that you drink, the more you damage your liver. ALD is the earliest stage of alcohol-related liver disease. The next stages are alcoholic hepatitis and cirrhosis.

The cause of MASLD is unknown, but it is more common in people who:

• Have type 2 diabetes and prediabetes
• Have obesity
• Are middle aged or older (although children can also get it)
• Have high cholesterol or triglycerides
• Have high blood pressure
• Take certain medicines, such as corticosteroids and some cancer medicines
• Have certain metabolic disorders, including metabolic syndrome
• Have rapid weight loss
• Have certain infections, such as hepatitis C
• Have been exposed to certain harmful substances

MASLD is the most common chronic (long-term) liver disease due to increasing rates of obesity, type 2 diabetes, and high cholesterol.

ALD only happens in people who are heavy drinkers, especially those who have been drinking for a long period of time. The risk is higher for people who drink heavily and are women, have obesity, or have certain gene changes (known as variants or mutations).

Both MASLD and ALD usually have few or no symptoms. If you do have symptoms, you may feel tired or have discomfort in the upper right side of your abdomen (belly).

Because there are often no symptoms, it's not easy to find steatotic liver disease. Your health care provider may suspect you have it if you have abnormal results on liver tests. To make a diagnosis, your provider may use:

• Your medical history. This may include asking about your alcohol use and any medicines you take.
• A physical exam. This may include checking your height and weight. Your provider may also check your body for signs of liver disease such as an enlarged liver or jaundice, a condition that causes your skin and whites of your eyes to turn yellow.
• Blood tests. These may include liver function tests and blood count tests.
• Imaging tests. These tests may be used to check for fat in the liver and for fibrosis.
• A biopsy. In some cases, a biopsy may be done to confirm the diagnosis and check for liver damage.

The first step in treating MASLD is usually weight loss. Losing weight can reduce fat in the liver, inflammation, and fibrosis. If your provider thinks that a certain medicine is the cause of your MASLD, they may tell you to stop or switch medicines. But don't stop taking any medicines unless your provider tells you to.

More studies are needed to see whether certain medicines are safe and effective to treat MASLD. Currently, no medicines are approved for treatment.

The most important part of treating ALD is to stop drinking alcohol. If you need help, you may benefit from counseling, a recovery program, or medicines that reduce cravings or make you feel sick if you drink alcohol.

Both ALD and one type of MASLD can lead to cirrhosis. Health problems caused by cirrhosis may be treated with medicines, surgery, and other medical procedures. If cirrhosis leads to liver failure, you may need a liver transplant.

If you have any type of steatotic liver disease, there are some lifestyle changes that can help:

• Eat a healthy diet, limiting salt and sugar, plus eating lots of fruits, vegetables, and whole grains.
• Talk with your provider about vaccinations. If you have chronic liver disease you are more likely to get infections. Your provider may recommend vaccinations for hepatitis A and B, the flu and pneumococcal disease.
• Get regular exercise, which can help you lose weight and reduce fat in the liver.

Check with your provider before using dietary supplements, such as vitamins, or any complementary or alternative medicines or medical practices. Some supplements or herbal remedies can damage the liver.

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair system for the body. There are two main types of stem cells: embryonic stem cells and adult stem cells.

Stem cells are different from other cells in the body in three ways:

• They can divide and renew themselves over a long time
• They are unspecialized, so they cannot do specific functions in the body
• They have the potential to become specialized cells, such as muscle cells, blood cells, and brain cells

Doctors and scientists are excited about stem cells because they could help in many different areas of health and medical research. Studying stem cells may help explain how serious conditions such as birth defects and cancer come about. Stem cells may one day be used to make cells and tissues for therapy of many diseases. Examples include Parkinson's disease, Alzheimer's disease, spinal cord injury, heart disease, diabetes, and arthritis.

NIH: National Institutes of Health

You may have heard of anabolic steroids, which can have harmful effects. But there's another type of steroid - sometimes called a corticosteroid - that treats a variety of problems. These steroids are similar to hormones that your adrenal glands make to fight stress associated with illnesses and injuries. They reduce inflammation and affect the immune system.

You may need to take corticosteroids to treat:

• Arthritis
• Asthma
• Autoimmune diseases such as lupus and multiple sclerosis
• Skin conditions such as eczema and rashes
• Some kinds of cancer

Steroids are strong medicines, and they can have side effects, including weakened bones and cataracts. Because of this, you usually take them for as short a time as possible.

Ultraviolet (UV) rays are an invisible form of radiation. They can pass through your skin and damage your skin cells. Sunburns are a sign of skin damage. Suntans aren't healthy, either. They appear after the sun's rays have already killed some cells and damaged others. UV rays can cause skin damage during any season or at any temperature. They can also cause eye problems, wrinkles, skin spots, and skin cancer.

To protect yourself :

• Stay out of the sun when it is strongest (between 10 a.m. and 2 p.m.)
• Use sunscreen with an SPF of 15 or higher
• Wear protective clothing
• Wear wraparound sunglasses that provide 100% UV ray protection
• Avoid sunlamps and tanning beds

Check your skin regularly for changes in the size, shape, color, or feel of birthmarks, moles, and spots. Such changes are a sign of skin cancer.

Food and Drug Administration

Testicles, or testes, make male hormones and sperm. They are two egg-shaped organs inside the scrotum, the loose sac of skin behind the penis. It's easy to injure your testicles because they are not protected by bones or muscles. Men and boys should wear athletic supporters when they play sports.

You should examine your testicles monthly and seek medical attention for lumps, redness, pain or other changes. Testicles can get inflamed or infected. They can also develop cancer. Testicular cancer is rare and highly treatable. It usually happens between the ages of 15 and 40.