Effects of Alcohol on Weight Change

Part 1: Comprehensive, evidence-based guide to effects of alcohol on weight gain or loss.

By Dr. Karen Vieira, PhD MSM

HEALTH According to the American Psychiatric Association, substance abuse is the excessive use of substances, including alcohol and drugs, that cause an individual to suffer from clinical impairments as well as the dramatic loss of academic, professional, and social skills [1].

Substance abuse also dramatically alters the diet and in most cases, it leads to irregular eating patterns and poor nutrition. As a result, previously healthy adolescents and adults may begin to experience significant health problems shortly after the substance abuse begins.

Effects of Alcohol on Weight Change

This guide will describe the negative effects that substance abuse can have on weight and how fluctuations in weight can lead to serious health problems.

Substance Abuse Affects Metabolism

Metabolism refers to the way the body breaks down food and uses it for nutrients and energy. Cells throughout the body must receive adequate amounts of nutrients, including sugar in the form of glucose to use for energy, growth, and repair from damage. Poor diet and nutrition, which often occurs secondarily to substance abuse, can lead to brain damage, organ damage, and different types of diseases [2,3].

Effects of Alcohol on Weight Change

The body cannot store alcohol, so once it is consumed it is quickly broken down to facilitate excretion from the body. Alcohol does not contain any nutrients, but it does contain ‘empty’ calories that often make people feel as if they are full, especially if they consume large quantities of it. Large amounts of alcohol damage the intestinal tract, which then decreases the body’s ability to absorb and utilize vitamins, minerals and other nutrients from the food that is eaten [4].

Amino acids, in particular, are an essential source of nutrients that are contained in protein-rich foods. Amino acids are distributed throughout the body in order to boost energy production, cell growth and repair. High levels of alcohol in the body cause both the intestines and the liver to assign precious cellular resources to the removal of alcohol. This prevents nutrients, such as amino acids, from being properly utilized by the body. In a healthy body, an assortment of amino acids and other nutrients are needed to avoid organ damage and disease. Prolonged and excessive alcohol consumption interferes with these processes.

High levels of alcohol in the blood may also slow down processes in the body such as digestion, which would normally stimulate the release of vitamins, minerals, sugar, and amino acids from foods so that they can be used by cells for proper growth, development and repair.

Alcohol Disrupts Liver Function

Alcohol abuse speeds up metabolism due to the fact that the liver has to work hard to break down the alcohol and remove it from the body [3]. However, this hinders the liver from breaking down carbohydrates and releasing nutrients, such as glucose (sugar), for cells throughout the body.

Effects of Alcohol on Weight Change

The liver also stores excess glucose as fat that can be used as an energy source when it is needed. Unfortunately, when the liver has large amounts of alcohol to process due to alcohol abuse, it does not release the stored glucose and instead begins to swell. When fat cells accumulate in the liver due to alcohol abuse, a phenomenon known as alcoholic steatohepatitis may also develop. This condition may be asymptomatic during the early stages of liver damage, but flu-like symptoms such as fatigue, fever, nausea, vomiting and a loss of appetite usually occur during the late stage of liver damage [5].

Liver damage causes specific enzymes such as bilirubin to be released into the blood and alcoholic steatohepatitis is typically diagnosed if a physician detects elevated levels of liver enzymes in the blood. Once this condition has been diagnosed, there is a high risk of dying due to liver failure [5].

Effects of Alcohol on Weight Change

In addition, the alcohol that is processed by the liver releases toxic substances which activate the immune system, causing it to produce proteins that seek to destroy these substances. However, the accumulation of the toxins that are released from the alcohol along with the buildup of proteins that work toward removing the toxins from the body cause inflammation [6], especially when alcohol is consumed regularly.

Although the body attempts to quickly remove the toxins from the body, if a person chronically abuses alcohol these dangerous substances continue to accumulate and begin to affect cells in various organs. This leads to liver, kidney, heart and brain damage, among other problems such as atherosclerosis [6].

"The absence of symptoms often makes people think that their alcohol abuse is not causing them any physical harm, but this is usually not the actual case." In some people, it takes decades for liver damage that has been caused by alcohol abuse to present physical symptoms. The absence of symptoms often makes people think that their alcohol abuse is not causing them any physical harm, but this is usually not the actual case. Early signs of liver damage or disease include: nausea, vomiting, abdominal pain, diarrhea and fatigue. Sometimes these types of symptoms may be mistaken for other health problems such as a stomach bug or virus, but for people who abuse alcohol it may actually be the first sign of liver damage.

Signs and symptoms that occur when liver damage has reached the late stage include:

  • Loss of appetite
  • Jaundice or yellow skin
  • Weakness
  • Extreme fatigue
  • Pruritus (Itchy skin)
  • Skin that bruises easily
  • Swelling of the abdomen, legs or ankles
  • Portal hypertension
  • Ascites (peritoneal fluid accumulation)
  • Intestinal bleeding
  • Cirrhosis (permanent liver damage)
  • Liver cancer

Getting treatment for alcohol abuse and dramatically decreasing the amount of alcohol that is consumed can help reverse the early stages of liver damage. Moreover, if liver damage reaches a late stage, refraining from drinking alcohol will slow the progression of the damage.

The Effects of Alcohol Abuse on Body Weight

Alcohol abuse not only disrupts the body’s ability to extract nutrients from food and transport them to different parts of the body, but it also causes intestinal damage. When the intestines become irritated, digestive processes either slow down or stop and this may lead to a loss of appetite, constipation and an intestinal blockage. All of these symptoms cause people to eat less and begin to lose weight [4].

Eating less means that adequate amounts of nutrients will not be consumed and as a person’s weight continues to drop, poor nutrition may begin to cause a number of health problems that include [7]:

  • Eating disorders
  • Tooth decay
  • High cholesterol
  • Heart disease
  • Heart attack and stroke
  • High blood pressure
  • Osteoporosis
  • Depression
  • Seizures
  • Certain types of cancer (e.g., liver)
  • Increased risk of death
Effects of Alcohol on Weight Change

Consuming alcohol on an empty stomach is another harmful habit that can cause blood sugar to drop to dangerously low levels. Overtime, alcohol abuse may even lead to glucose intolerance and type 2 diabetes because the liver focuses too much energy on processing and excreting the toxins that alcohol produces [8].

Alcohol abuse can also lead to fluctuations in weight due to its effect on the brain. If the stomach is empty, alcohol can quickly leave the stomach and reach the brain. This process is slowed when there is food in the stomach, but if a large amount of alcohol is consumed, it can still reach the bloodstream, liver, and the brain much more quickly than the nutrients contained in the food.

The liver takes about two hours to process the alcohol that is contained in one alcoholic beverage such as a glass of wine or a beer. If alcohol has been consumed excessively, it circulates throughout the body until the liver can process it. This means that, in the interim, the brain and other organs (e.g., kidney and heart) receive high levels of toxins that are released from alcohol.

Effects of Alcohol on Weight Change

Alcohol subsequently affects the brain by causing vision, speech, judgment and reasoning problems. These types of side effects may cause some individuals to eat less, forget to eat, overeat or eat foods that they would normally avoid. Forgetting to eat properly can quickly lead to weight loss, but overeating can also lead to weight gain, obesity, type 2 diabetes and other conditions such as heart disease [9].

Type 2 diabetes that develops due to alcohol abuse and weight loss is the result of not eating enough food, which leads to persistently low blood sugar levels and glucose intolerance. The body’s intolerance to glucose (sugar) develops because the liver avoids utilizing glucose in order to continuously process the high amount of alcohol that has been consumed.

Effects of Alcohol on Weight Change

Conversely, alcohol abuse that leads to obesity and type 2 diabetes is the result of persistently high blood sugar levels. Overeating means fats and carbohydrates are being consumed faster than the body can break them down and excrete the waste. This leads to high levels of glucose (sugar) in the blood that the liver cannot immediately process because it is already trying to remove the excess alcohol. As a result, obesity in combination with uncontrolled sugar levels can eventually also cause type 2 diabetes [9].

In general, alcohol abuse can lead to dangerous fluctuations in weight that may eventually cause irreversible organ damage and disorders such as diabetes. For instance, once an individual has been diagnosed with diabetes, this becomes a lifelong condition that must permanently be treated. Similarly, late stage liver disease that develops due to alcohol abuse is irreversible, although refraining from drinking alcohol can slow down the progression of the disease. Steps should be taken early to avoid the harmful effects of alcohol abuse.

The Effects of Alcohol on Maternal Nutrition And Birth Weight

Effects of Alcohol on Weight Change

If alcohol is consumed during pregnancy, it can cause poor nutrition for the mother as well as the unborn baby. More specifically, consuming alcohol while pregnant can lead to physical and mental problems as well as acute alcohol withdrawal symptoms in the newborn child [10]. If alcohol or drugs are consumed during a pregnancy, the mother’s poor diet may hinder the proper growth and development of the baby and cause low birth weight [11].

Ways To Consume Alcohol Safely And Maintain A Healthy Weight

Drinking alcohol occasionally and in moderation usually does not cause health problems, but consuming large amounts on a regular basis frequently constitutes alcohol abuse and ushers in a number of different health problems. Here are some helpful strategies for consuming alcohol safely:

Eat healthy meals before drinking in moderation. In addition, eat snacks that are low in salt and fat in between drinks as this slows down the body’s absorption of alcohol.

Take days off from drinking alcohol, even if only small amounts of alcohol are consumed regularly. This deters the development of alcohol abuse and addiction patterns, as well as the onset of organ damage associated with habitual alcohol consumption.

Keep track of the types of drinks that are consumed as some drinks contain more alcohol than others. Keeping track also provides an indication of when the drinking should stop.

The Importance of Alcohol Abuse Treatment

In addition to causing harmful fluctuations in weight, alcohol abuse can lead to multiple major organ damage, especially to the liver, kidneys and heart  [12]. People who have health problems such as arthritis or diabetes tend to worsen their symptoms and even speed up the progression of their condition through alcohol abuse, with any associated weight changes potentially compounding the damage done. Part 2 of this article will present the effects of drugs on weight change.

About The Author
Karen Vieira

Dr. Karen Vieira, PhD MSM is a research scientist with a PhD in Biomedical Sciences from the University of Florida College of Medicine Department of Biochemistry & Molecular Biology. She has done clinical and laboratory research on diseases, cellular functioning and nutritional supplements. Her focus is helping people make dietary and lifestyle changes that prevent, cure or improve health conditions.

Tags: doctors, nurses, nutritionists, rehabilitation

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