Excessive alcohol intake is associated with an elevated risk of alcoholic liver disease (ALD), heart failure, some cancers, and accidental injury, and is a leading cause of preventable death in industrialized countries. However, extensive research has shown that moderate alcohol intake is associated with health benefits, including less cardiovascular disease, diabetes, and hypertension.

An understanding of the inverse relationship between alcohol consumption and atherosclerosis was understood as early as 1904. The observation of a lower risk of cardiovascular disease (CVD) in France despite a diet rich in saturated fat was labeled the French Paradox. While much concerning this paradox remains unclear, some have suggested that the higher consumption of red wine in France results in lower CVD. Although the reduced incidence of CVD disease associated with moderate alcohol consumption is well established, many physicians have been wary of promoting the use of alcohol for this benefit considering the many negative effects of excessive alcohol consumption.

The long-term effects of alcohol (also known formally as ethanol) consumption range from cardioprotective health benefits for low to moderate alcohol consumption in industrialized societies with higher rates of cardiovascular disease to severe detrimental effects in cases of chronic alcohol abuse. Health effects associated with alcohol intake in large amounts include an increased risk of alcoholism, malnutrition, chronic pancreatitis, ], and cancer. In addition, damage to the central nervous system and peripheral nervous system can occur from chronic alcohol abuse. The long-term use of alcohol is capable of damaging nearly every organ and system in the body. The developing adolescent brain is particularly vulnerable to the toxic effects of alcohol. In addition, the developing fetal brain is also vulnerable, and fetal alcohol spectrum disorders (FASDs) may result if pregnant mothers consume alcohol.

The inverse relation in Western cultures between alcohol consumption and cardiovascular disease has been known for over 100 years. Many physicians do not promote alcohol consumption, however, given the many health concerns associated with it, some suggest that alcohol should be regarded as a recreational drug, and promote exercise and good nutrition to combat cardiovascular disease. Others have argued that the benefits of moderate alcohol consumption may be outweighed by other increased risks, including those of injuries, violence, fetal damage, liver disease, and certain forms of cancer. Alcohol liver disease (ALD) accounted for four fifths of all chronic diseases in Ireland in 2013.

Withdrawal effects and dependence are also almost identical. Alcohol at moderate levels has some positive and negative effects on health. The negative effects include increased risk of liver diseases, oropharyngeal cancer, esophageal cancer and pancreatitis. Conversely moderate intake of alcohol may have some beneficial effects on gastritis and cholelithiasis. Of the total number of deaths and diseases caused by alcohol, most happen to the majority of the population who are moderate drinkers, rather than the heavy drinker minority. Chronic alcohol misuse and abuse has serious effects on physical and mental health. Chronic excess alcohol intake, or alcohol dependence, can lead to a wide range of neuropsychiatric or neurological impairment, cardiovascular disease, liver disease, and malignant neoplasms. The psychiatric disorders which are associated with alcoholism include major depression, dysthymia, mania, hypomania, panic disorder, phobias, generalized anxiety disorder, personality disorders, schizophrenia, suicide, neurologic deficits (e.g. impairments of working memory, emotions, executive functions, visuospatial abilities and gait and balance) and brain damage. Alcohol dependence is associated with hypertension, coronary heart disease, and ischemic stroke, cancer of the respiratory system, and also cancers of the digestive system, liver, breast and ovaries. Heavy drinking is associated with liver disease, such as cirrhosis. Excessive alcohol consumption can have a negative impact on aging.

Recent studies have focused on understanding the mechanisms by which moderate alcohol consumption confers cardiovascular benefit.

Warning signs of alcoholism include the consumption of increasing amounts of alcohol and frequent intoxication, preoccupation with drinking to the exclusion of other activities, promises to quit drinking and failure to keep those promises, the inability to remember what was said or done while drinking (colloquially known as "blackouts"), personality changes associated with drinking, denial or the making of excuses for drinking, the refusal to admit excessive drinking, dysfunction or other problems at work or school, the loss of interest in personal appearance or hygiene, marital and economic problems, and the complaint of poor health, with loss of appetite, respiratory infections, or increased anxiety.

Drinking enough to cause a blood alcohol concentration (BAC) of 0.03–0.12% typically causes an overall improvement in mood and possible euphoria (a "happy" feeling), increased self-confidence and sociability, decreased anxiety, a flushed, red appearance in the face and impaired judgment and fine muscle coordination. A BAC of 0.09% to 0.25% causes lethargy, sedation, balance problems and blurred vision. A BAC of 0.18% to 0.30% causes profound confusion, impaired speech (e.g. slurred speech), staggering, dizziness and vomiting. A BAC from 0.25% to 0.40% causes stupor, unconsciousness, anterograde amnesia, vomiting (death may occur due to inhalation of vomit (pulmonary aspiration) while unconscious and respiratory depression (potentially life-threatening). A BAC from 0.35% to 0.80% causes a coma (unconsciousness), life-threatening respiratory depression and possibly fatal alcohol poisoning. With all alcoholic beverages, drinking while driving, operating an aircraft or heavy machinery increases the risk of an accident; many countries have penalties for drunk driving.

Essential tremors—or, in the case of essential tremors on a background of family history of essential tremors, familial tremors—can be temporarily relieved in up to two-thirds of patients by drinking small amounts of alcohol.

Ethanol is known to activate aminobutyric acid type A (GABAA) and inhibit N-methyl-D-aspartate (NMDA) glutamate receptors, which are both implicated in essential tremor pathology and could underlie the ameliorative effects. Additionally, the effects of ethanol have been studied in different animal essential tremor models. (For more details on this topic, see Essential tremor.)

Alcohol (also known as ethanol) has a number of effects on health. Short-term effects of alcohol consumption include intoxication and dehydration. Long-term effects of alcohol consumption include changes in the metabolism of the liver and brain and alcoholism. Alcohol intoxication affects the brain, causing slurred speech, clumsiness, and delayed reflexes. Alcohol stimulates insulin production, which speeds up glucose metabolism and can result in low blood sugar, causing irritability and possibly death for diabetics. A 2014 World Health Organization report found that harmful alcohol consumption caused about 3.3 million deaths annually worldwide.

However, some effects of alcohol consumption are beneficial. Although even moderate alcohol consumption increased the risk of death in younger people, it has been shown to "decrease" the risk of death for individuals ages 55+ (due to decreased risk of ischemic heart disease).

The median lethal dose of alcohol in test animals is a blood alcohol content of 0.45%. This is about six times the level of ordinary intoxication (0.08%), but vomiting or unconsciousness may occur much sooner in people who have a low tolerance for alcohol. The high tolerance of chronic heavy drinkers may allow some of them to remain conscious at levels above 0.40%, although serious health hazards are incurred at this level.

Alcohol also limits the production of vasopressin (ADH) from the hypothalamus and the secretion of this hormone from the posterior pituitary gland. This is what causes severe dehydration when alcohol is consumed in large amounts. It also causes a high concentration of water in the urine and vomit and the intense thirst that goes along with a hangover.

Stress, hangovers, and the oral contraceptive pill may increase the desire for alcohol because these things will lower the level of testosterone and alcohol will acutely elevate it. Tobacco has the same effect of increasing the craving for alcohol.

The impact of alcohol on aging is multifaceted. Evidence shows that alcoholism or chronic alcohol consumption can cause both accelerated (or premature) aging – in which symptoms of aging appear earlier than normal – and exaggerated aging, in which the symptoms appear at the appropriate time but in a more exaggerated form. The effects of alcohol abuse/misuse on the aging process include hypertension, cardiac dysrhythmia, cancers, gastrointestinal disorders, neurocognitive deficits, bone loss, and emotional disturbances especially depression. On the other hand, research also shows that drinking moderate amounts of alcohol may protect healthy adults from developing coronary heart disease. The American Heart Association cautions people not to start drinking, if you are not already drinking.

Alcohol tolerance refers to the bodily responses to the functional effects of ethanol in alcoholic beverages. This includes direct tolerance, speed of recovery from insobriety and resistance to the development of alcoholism.

Alcohol is a potent neurotoxin. The National Institute on Alcohol Abuse and Alcoholism has found, "Alcoholism may accelerate normal aging or cause premature aging of the brain." Another report by the same agency found, "Chronic alcohol consumption, as well as chronic glucocorticoid exposure, can result in premature and/or exaggerated aging." Specifically, alcohol activates the HPA axis, causing glucocorticoid secretion and thus elevating levels of stress hormones in the body. Chronic exposure to these hormones results in an acceleration of the aging process, which is associated with "gradual, but often dramatic, changes over time in almost every physiological system in the human body. Combined, these changes result in decreased efficiency and resiliency of physiological function." Chronic stress and chronic heavy alcohol use cause a similar premature aging effect, including nerve cell degeneration in the hippocampus.

Binge drinking, or heavy episodic drinking, is a modern epithet for drinking alcoholic beverages with an intention of becoming intoxicated by heavy consumption of alcohol over a short period of time.

Binge drinking is a style of drinking that is popular in several countries worldwide, and overlaps somewhat with social drinking since it is often done in groups. The degree of intoxication, however, varies between and within various cultures that engage in this practice. A binge on alcohol can occur over hours, last up to several days, or in the event of extended abuse, even weeks. Due to the long-term effects of alcohol misuse, binge drinking is considered to be a major public health issue.

Binge drinking is associated with a profound social harm, economic costs as well as increased disease burden. Binge drinking is more common in males, during adolescence and young adulthood. Heavy regular binge drinking is associated with adverse effects on neurologic, cardiac, gastrointestinal, hematologic, immune, musculoskeletal organ systems as well as increasing the risk of alcohol induced psychiatric disorders. A US-based review of the literature found that up to one-third of adolescents binge-drink, with six percent reaching the threshold of having an alcohol-related substance use disorder. Approximately one in 25 women binge-drinks during pregnancy, which can lead to fetal alcohol syndrome and fetal alcohol spectrum disorders. Binge drinking during adolescence is associated with traffic accidents and other types of accidents, violent behavior as well as suicide. The more often a child or adolescent binge drinks and the younger they are the more likely that they will develop an alcohol use disorder including alcoholism. A large number of adolescents who binge-drink also consume other psychotropic substances.

The short-term effects of alcohol consumption range from a decrease in anxiety and motor skills at lower doses to unconsciousness, anterograde amnesia, and central nervous system depression at higher doses. Cell membranes are highly permeable to alcohol, so once alcohol is in the bloodstream it can diffuse into nearly every cell in the body.

The concentration of alcohol in blood is measured via blood alcohol content (BAC). The amount and circumstances of consumption play a large part in determining the extent of intoxication; for example, eating a heavy meal before alcohol consumption causes alcohol to absorb more slowly. Hydration also plays a role, especially in determining the extent of hangovers. After excessive drinking, unconsciousness can occur and extreme levels of consumption can lead to alcohol poisoning and death (a concentration in the blood stream of 0.40% will kill half of those affected). Alcohol may also cause death indirectly, by asphyxiation from vomit.

Alcohol can greatly exacerbate sleep problems. During abstinence, residual disruptions in sleep regularity and sleep patterns are the greatest predictors of relapse.

The health effects of wine are mainly determined by its active ingredient alcohol. Some studies found that drinking small quantities of alcohol (up to one standard drink per day for women and one to two drinks per day for men) is associated with a decreased risk of heart disease, stroke, diabetes mellitus, metabolic syndrome and early death. However, other studies found no such effect. Drinking more than the standard drink amount increases the risk of heart disease, high blood pressure, atrial fibrillation, stroke and cancer. Mixed results are also observed in light drinking and cancer mortality.

Risk is greater in younger people due to binge drinking which may result in violence or accidents. About 88,000 deaths in the US are estimated to be due to alcohol each year. Alcoholism reduces a person's life expectancy by around ten years and excessive alcohol use is the third leading cause of early death in the United States. According to systematic reviews and medical associations, people who are nondrinkers should not start drinking wine.

Wine has a long history of use as an early form of medication, being recommended variously as a safe alternative to drinking water, an antiseptic for treating wounds, a digestive aid, and as a cure for a wide range of ailments including lethargy, diarrhea and pain from child birth. Ancient Egyptian papyri and Sumerian tablets dating back to 2200 BC detail the medicinal role of wine, making it the world's oldest documented human-made medicine. Wine continued to play a major role in medicine until the late 19th and early 20th century, when changing opinions and medical research on alcohol and alcoholism cast doubt on its role as part of a healthy lifestyle.

From the ICD-9 database:

- A chronic disease in which a person craves drinks that contain alcohol and is unable to control his or her drinking. A person with this disease also needs to drink greater amounts to get the same effect and has withdrawal symptoms after stopping alcohol use. Alcoholism affects physical and mental health, and can cause problems with family, friends, and work.

- A disorder characterized by a pathological pattern of alcohol use that causes a serious impairment in social or occupational functioning.

- A primary, chronic disease with genetic, psychosocial, and environmental factors influencing its development and manifestations. The disease is often progressive and fatal. It is characterized by impaired control over drinking, preoccupation with the drug alcohol, use of alcohol despite adverse consequences, and distortions in thinking, most notably denial. Each of these symptoms may be continuous or periodic. (morse & flavin for the joint commission of the national council on alcoholism and drug dependence and the american society of addiction medicine to study the definition and criteria for the diagnosis of alcoholism: in jama 1992;268:1012-4)

- For most adults, moderate alcohol use is probably not harmful. However, about 18 million adult Americans are alcoholics or have alcohol problems. Alcoholism is a disease with four main features:

- craving - a strong need to drink

- loss of control - not being able to stop drinking once you've started

- physical dependence - withdrawal symptoms, such as nausea, sweating, or shakiness when you don't drink

- tolerance - the need to drink greater amounts of alcohol to feel the same effect

- Temporary mental disturbance marked by muscle incoordination and paresis as the result of excessive alcohol ingestion.

According to the DSM-IV criteria for alcohol dependence, at least three out of seven of the following criteria must be manifest during a 12-month period:

- Tolerance

- Withdrawal symptoms or clinically defined alcohol withdrawal syndrome

- Use in larger amounts or for longer periods than intended

- Persistent desire or unsuccessful efforts to cut down on alcohol use

- Time is spent obtaining alcohol or recovering from effects

- Social, occupational and recreational pursuits are given up or reduced because of alcohol use

- Use is continued despite knowledge of alcohol-related harm (physical or psychological)

Stolle, Sack and Thomasius define binge drinking as episodic excessive drinking. There is currently no worldwide consensus on how many drinks constitute a "binge", but in the United States, the term has been described in academic research to mean consuming five or more standard drinks (male), or four or more drinks (female), over a 2-hour period. In 2015, the US Centers for Disease Control and Prevention, citing the National Institute on Alcohol Abuse and Alcoholism, defines binge drinking as "a pattern of drinking that brings a person’s blood alcohol concentration (BAC) to 0.08 grams percent or above. This typically happens when men consume 5 or more drinks, and when women consume 4 or more drinks, in about 2 hours." and estimated that about 16% of American adults met these binge drinking criteria four times per month. One 2001 definition from the publication "Psychology of Addictive Behavior" states that 5 drinks for men and 4 drinks for women must be consumed on one occasion at least once in a two-week period for it to be classed as binge drinking. This is colloquially known as the "5/4 definition", and depending on the source, the timeframe can vary. In the United Kingdom, binge drinking is defined by one academic publication as drinking more than twice the daily limit, that is, drinking eight units or more for men or six units or more for women (roughly equivalent to five or four American standard drinks, respectively). In Australia, binge drinking is also known as risky single occasion drinking (RSOD) and can be classified by the drinking of seven or more standard drinks (by males) and 5 or more standard drinks (by females) within a single day. When BEACH (Bettering the Evaluation of care and health) conducted a study which gathered information of people over the age of 18, it defined binge drinkers as those who consumed six or more standard drinks on one occasion whether that be weekly or monthly.

The above definitions are limited in that they do not take into account the time period over which the drinking occurs or the body mass of the person drinking. A person could be defined as a binge drinker even if he or she never becomes intoxicated. The term, however, has succeeded in drawing public awareness to the problem of excess drinking..

Other, less common definitions rely on blood alcohol concentration (BAC). For example, the National Institute on Alcohol Abuse and Alcoholism (NIAAA) defines the term "binge drinking" as a pattern of drinking that brings a person’s blood alcohol concentration (BAC) to 0.08 grams percent or above. Whatever the numerical definition used, heavy drinking or rapid consumption over a short period of time with the intention of becoming intoxicated is often implied when the term is used colloquially, since four or five drinks consumed over the course of a whole day and as an accompaniment to meals will not have the same effects as the same amount consumed over a couple of hours on an empty stomach.

An alternative colloquial term for binge drinking, "going on a bender", formerly implied a drinking spree of several days.

Lifestyle diseases are defined as diseases linked with the way people live their life. This is commonly caused by alcohol, drug and smoking abuse as well as lack of physical activity and unhealthy eating. Diseases that impact on our lifestyle are heart disease, stroke, obesity and type II diabetes. The diseases that appear to increase in frequency as countries become more industrialized and people live longer. They can include Alzheimer's disease, arthritis, atherosclerosis, asthma, cancer, chronic liver disease or cirrhosis, chronic obstructive pulmonary disease, type 2 diabetes, heart disease, metabolic syndrome, chronic renal failure, osteoporosis, stroke, depression, obesity and vascular dementia. In the U.K the death rate is four times higher from respiratory disease caused by an unhealthy lifestyle

Some commenters maintain a distinction between diseases of longevity and diseases of civilization. Certain diseases, such as diabetes, dental caries and asthma, appear at greater rates in young populations living in the "western" way; their increased incidence is not related to age, so the terms cannot accurately be used interchangeably for all diseases.

Alcoholic polyneuropathy (A.K.A alcohol leg) is a neurological disorder in which multiple peripheral nerves throughout the body malfunction simultaneously. It is defined by axonal degeneration in neurons of both the sensory and motor systems and initially occurs at the distal ends of the longest axons in the body. This nerve damage causes an individual to experience pain and motor weakness, first in the feet and hands and then progressing centrally. Alcoholic polyneuropathy is caused primarily by chronic alcoholism; however, vitamin deficiencies are also known to contribute to its development. This disease typically occurs in chronic alcoholics who have some sort of nutritional deficiency. Treatment may involve nutritional supplementation, pain management, abstaining from alcohol.

Alcohol tolerance is increased by regular drinking. This reduced sensitivity requires that higher quantities of alcohol be consumed in order to achieve the same effects as before tolerance was established. Alcohol tolerance may lead to (or be a sign of) alcohol dependency.

Heavy alcohol consumption over a period of years can lead to "reverse tolerance". A liver can be damaged by chronic alcohol use, leading to a buildup of fat and scar tissue. The reduced ability of such a liver to metabolize or break down alcohol means that small amounts can lead to a high blood alcohol concentration (BAC) and more rapid intoxication.

Alcoholic polyneuropathy usually has a gradual onset over months or even years although axonal degeneration often begins before an individual experiences any symptoms. An early warning sign (prodrome) of the possibility of developing alcoholic polyneuropathy, specially in a chronic alcoholic, would be weight loss because this usually signifies a nutritional deficiency that can lead to the development of the disease.

The disease typically involves sensory and motor loss, as well as painful physical perceptions (paresthesias), though all sensory modalities may be involved. Symptoms that affect the sensory and motor systems seem to develop symmetrically. For example, if the right foot is affected, the left foot is affected simultaneously or soon becomes affected. In most cases, the legs are affected first, followed by the arms. The hands usually become involved when the symptoms reach above the ankle. This is called a stocking-and-glove pattern of sensory disturbances.

Polyneuropathy spans a large range of severity. Some cases are seemingly asymptomatic and may only be recognized on careful examination. The most severe cases may cause profound physical disability.

The key of FASD can vary between individuals exposed to alcohol during pregnancy. While consensus exists for the definition and diagnosis of FAS, minor variations among the systems lead to differences in definitions and diagnostic cut-off criteria for other diagnoses across the FASD continuum. The central nervous system damage criteria particularly lack clear consensus. A working knowledge of the key features is helpful in understanding FASD diagnoses and conditions, and each is reviewed with attention to similarities and differences across the four diagnostic systems. More than 400 problems, however, can occur with FASD.

Extensive epidemiological studies have demonstrated the cardioprotective effect of alcohol consumption. However the mechanism by which this occurs is not fully understood. Research has suggested several possible mechanisms, including the following.

There is a lack of medical consensus about whether moderate consumption of beer, wine, or distilled spirits has a stronger association with heart disease. Studies suggest that each is effective, with none having a clear advantage. Most researchers now believe that the most important ingredient is the alcohol itself.

The American Heart Association has reported that "More than a dozen prospective studies have demonstrated a consistent, strong, dose-response relation between increasing alcohol consumption and decreasing incidence of CHD (coronary heart disease). The data are similar in men and women in a number of different geographic and ethnic groups. Consumption of one or two drinks per day is associated with a reduction in risk of approximately 30% to 50%".

Heart disease is the largest cause of mortality in the United States and many other countries. Therefore, some physicians have suggested that patients be informed of the potential health benefits of drinking alcohol in moderation, especially if they abstain and alcohol is not contraindicated. Others, however, argue against the practice in fear that it might lead to heavy or abusive alcohol consumption. Heavy drinking is associated with a number of health and safety problems.

FASDs encompass a range of physical and neurodevelopmental problems that can result from prenatal alcohol exposure. The most severe condition is called fetal alcohol syndrome (FAS), which refers to individuals who have a specific set of birth defects and neurodevelopmental disorders characteristic of the diagnosis.

Some accept only FAS as a diagnosis, seeing the evidence as inconclusive with respect to other types. Partial fetal alcohol syndrome (pFAS) refers to individuals with a known, or highly suspected, history of prenatal alcohol exposure who have alcohol-related physical and neurodevelopmental deficits that don’t meet the full criteria for FAS. The subtypes of pFAS are alcohol-related neurodevelopmental disorder (ARND) and alcohol-related birth defects (ARBD). In addition to FAS, pFAS, ARND, and ARBD, any other conditions believed to be related to prenatal alcohol exposure, such as spontaneous abortion and sudden infant death syndrome (SIDS), are also considered to be on the spectrum of related disorders. It is unclear as of 2017 if identifying a FASD-related conditions benefits the individual.

Physical dependence can manifest itself in the appearance of both physical and psychological symptoms which are caused by physiological adaptions in the central nervous system and the brain due to chronic exposure to a substance. Symptoms which may be experienced during withdrawal or reduction in dosage include increased heart rate and/or blood pressure, sweating, and tremors. More serious withdrawal symptoms such as confusion, seizures, and visual hallucinations indicate a serious emergency and the need for immediate medical care. Sedative hypnotic drugs such as alcohol, benzodiazepines, and barbiturates are the only commonly available substances that can be fatal in withdrawal due to their propensity to induce withdrawal convulsions. Abrupt withdrawal from other drugs, such as opioids can cause an extremely physiologically and psychologically painful withdrawal that is very rarely fatal in patients of general good health and with medical treatment, but is more often fatal in patients with weakened cardiovascular systems; toxicity is generally caused by the often-extreme increases in heart rate and blood pressure (which can be treated with clonidine), or due to arrhythmia due to electrolyte imbalance caused by the inability to eat, and constant diarrhea and vomiting (which can be treated with loperamide and ondansetron respectively) associated with acute opioid withdrawal, especially in longer-acting substances where the diarrhea and emesis can continue unabated for weeks, although life-threatening complications are extremely rare, and nearly non-existent with proper medical management.

Diseases of affluence is a term sometimes given to selected diseases and other health conditions which are commonly thought to be a result of increasing wealth in a society. Psychologists' research is probing why affluent people enjoy better health. Epidemiological studies have confirmed the relationship between income, education and occupation on the one hand and health outcomes on the other. Studies have found that relative risk of death increased significantly as rank decreased. The message is simple: the lower a person's socioeconomic status, the greater their risk of both physical and psychological health problems.

Also referred to as the "Western disease" paradigm, these diseases are in contrast to so-called "diseases of poverty", which largely result from and contribute to human impoverishment. The modern diet and sedentary lifestyle is argued to be the blame for current levels of obesity, cardiovascular disease, high blood pressure, type 2 diabetes, osteoporosis, colorectal cancer, acne, gout,

depression, and diseases related to vitamin and mineral deficiencies. These diseases of affluence have vastly increased in prevalence since the end of World War II.

Examples of diseases of affluence include mostly chronic non-communicable diseases (NCDs) and other physical health conditions for which personal lifestyles and societal conditions associated with economic development are believed to be an important risk factor — such as type 2 diabetes, asthma, coronary heart disease, cerebrovascular disease, peripheral vascular disease, obesity, hypertension, cancer, alcoholism, gout, and some types of allergy.

They may also be considered to include depression and other mental health conditions associated with increased social isolation and lower levels of psychological well being observed in many developed countries. Many of these conditions are interrelated, for example obesity is thought to be a partial cause of many other illnesses.

In contrast, the diseases of poverty tend to be largely infectious diseases, or the result of poor living conditions. These include tuberculosis, asthma, and intestinal diseases. Increasingly, research is finding that diseases thought to be diseases of affluence also appear in large part in the poor. These diseases include obesity and cardiovascular disease and, coupled with infectious diseases, these further increase global health inequalities.

Diseases of affluence are predicted to become more prevalent in developing countries as diseases of poverty decline, longevity increases, and lifestyles change. In 2008, nearly 80% of deaths due to NCDs — including heart disease, strokes, chronic lung diseases, cancers and diabetes — occurred in low- and middle-income countries.

Most people with NAFLD have few or no symptoms. Patients may complain of fatigue, malaise, and dull right-upper-quadrant abdominal discomfort. Mild jaundice may be noticed, although this is rare. More commonly NAFLD is diagnosed following abnormal liver function tests during routine blood tests. By definition, alcohol consumption of over 20 g/day (about 25 ml/day of net ethanol) excludes the condition.

NAFLD is associated with insulin resistance and metabolic syndrome (obesity, combined hyperlipidemia, diabetes mellitus (type II), and high blood pressure).