Most people who are actively abusing substances have a significantly altered diet in addition to irregular eating patterns-both of which can lead to poor nutrition. Poor nutrition combined with substance abuse can really take a toll on the body and often results in significant health problems.

As far as weight gain goes, substance abuse can dramatically change your body's metabolism, and coupled with poor diet and malnutrition, substance abuse makes weight gain worse.

Substance Abuse and Your Metabolism

No matter what type of substance abuse – alcohol, drugs, or inhalants – the effect these have on a person's body weight can be a clear indicator of potentially serious health problems.

Alcoholic beverages tax every single body system. Because alcohol is so small, it can travel everywhere in your body, and it can even cross the blood-brain barrier. Once you take that first sip, alcohol can influence your absorption and metabolism of other nutrients, because your body essentially drops everything in order to breakdown and remove alcohol from your bloodstream.

Alcohol abuse can cause stomach and digestive symptoms, which can impair nutrient absorption, and over time this can lead to serious malnutrition and nutrient deficiencies. With excessive alcohol intake, it common for most of an individual's calories to be sourced from alcohol, which in turn displaces a balanced diet and prevents well-rounded nutrient intake.

However, for individuals who consume a large amount of alcohol daily, but still eat a varied diet each day, the calories can quickly add up and will eventually result in weight gain as a result.

One of the major side effects of alcohol abuse as it relates to weight gain is the stimulatory effect on appetite. It's easier to indulge in that extra piece of cake when you have had an adult beverage or two, which over time can add up to serious weight gain.

Most people are familiar with the liver damage that alcohol abuse can cause, which can lead to death in individuals who do not seek help with their condition. When the liver is flooded with alcohol to break down, slight swelling can result, and often fat cells will begin to develop in the liver, resulting in alcoholic steatohepatits. This condition can lead to liver failure and may require a liver transplant.

Chronic alcohol abuse over time can also cause pancreatitis, which typically leads to weight loss in substance abusers. Alcohol use is a major cause of acute pancreatitis, and accounts for at least 35% of cases in the hospital setting.

Narcotic Substance Abuse and Weight Gain

Alcohol aside, other types of substance abuse can also lead to weight gain. Narcotics (also called opioid pain relievers) have been shown to cause weight gain in people who abuse these substances. Opioids, such as heroin, are associated with weight gain, mainly because they disrupt the body's ability to control blood sugars. Approximately 1 million Americans are currently addicted to heroin in the United States alone. This class of drugs is associated with intense sugar cravings, in both human and animal studies, with weight gain occurring as a result. In female, methadone-maintained patients, sugar accounted for 31% of total caloric intake, and these women reported a heightened taste preference for high sugar foods.

While most of us may imagine the emaciated, starved look of heroin addicts, likely this is a consequence of spending money on drugs rather than food. When food was plentiful, a Swedish study found that 36% of heroin users were overweight, and 43% of methadone users were overweight.

Codeine is another common drug used as a pain reliever. This falls into the category of a 'depressant' and slows the body's metabolism. Other examples of depressants include alcohol, marijuana, and opiates as well. Depressants in general decrease appetite, with the exception of marijuana, which can sometimes result in increased food intake, famously referred to as 'the munchies'. This can definitely result in weight gain if it occurs regularly for an extended period of time.

Substance abuse that occurs with cocaine, ecstasy, and methamphetamine, often results in decreased appetite and a reduction in food intake, and resultant weight loss. However, after cessation of these substances, weight gain often occurs following a period of time.

The Truth About Quitting Smoking and Weight Gain

Most people are already aware one of the ingredients in cigarettes –nicotine – is highly addictive, which makes quitting smoking very difficult. The population with the highest rates of smoking also tends to be substance abusers and alcoholic beverage consumers, making it difficult to separate the effects of combining cigarettes and substance abuse on weight gain.

For many individuals, one of the deterrents from quitting smoking is the weight gain that often occurs as a result of quitting smoking. High nicotine cravings can affect appetite, and smoking instead of eating a healthy, balanced meal is never a good idea – because of the nutrients, including vitamins and minerals, that these individuals might miss in their day.

It's important to resist the urge to substitute food for smoking – as this can cause rapid weight gain. Also it's vital that weight gain does not become an excuse to avoid quitting smoking, because smoking puts individuals at a much higher risk for even more serious conditions, such as heart disease, stroke, heart attack, lung cancer, diabetes, asthma, and even death.

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