Starvation is a severe deficiency in caloric energy intake, below the level needed to maintain an organism's life. It is the most extreme form of malnutrition. In humans, prolonged starvation can cause permanent organ damage[1] and eventually, death. The term inanition[2] refers to the symptoms and effects of starvation. Starvation by outside forces is a crime according to international criminal law and may also be used as a means of torture or execution.
According to the World Health Organization (WHO), hunger is the single gravest threat to the world's public health.[3][4] The WHO also states that malnutrition is by far the biggest contributor to child mortality, present in half of all cases.[3] Undernutrition is a contributory factor in the death of 3.1 million children under five every year.[5] The results also demonstrates that as global hunger levels have stabilized, however, despite some progress in specific areas such as stunting and exclusive breastfeeding, an alarming number of people still face food insecurity and malnutrition. In fact, the world has been set back 15 years, with levels of undernourishment similar to those in 2008-2009, with between 713 and 757 million people undernourished in 2023, and over 152 million more than in 2019 when the mid-range was 733 million.[6]
The bloated stomach represents a form of malnutrition called kwashiorkor. The exact pathogenesis of kwashiorkor is not clear, as initially it was thought to relate to diets high in carbohydrates (e.g. maize) but low in protein.[7] While many patients have low albumin, this is thought to be a consequence of the condition. Possible causes such as aflatoxin poisoning, oxidative stress, immune dysregulation, and altered gut microbiota have been suggested.[8] Treatment can help mitigate symptoms such as the pictured weight loss and muscle wasting, however prevention is of utmost importance.[7]
Without any food, humans usually die in around 2 months.[9] There was a case when someone survived over a year (382 days) under medical supervision.[10] Lean people can usually survive with a loss of up to 18% of their body mass; obese people can tolerate more, possibly over 20%. Biological females survive longer than males.[11][12]
A girl during the Nigerian Civil War of the late 1960s, shown suffering the effects of severe hunger and malnutrition
The following are some of the symptoms of starvation:
Changes in behaviour or mental status
The beginning stages of starvation impact mental status and behaviours. These symptoms show up as irritable mood, fatigue, trouble concentrating, and preoccupation with food thoughts. People with those symptoms tend to be easily distracted and have no energy. Psychological effects are profound, including depression, anxiety, and a decrease in cognitive functions.
Physical signs
As starvation progresses, the physical symptoms set in. The timing of these symptoms depends on age, size, and overall health. It usually takes days to weeks, and includes weakness, fast heart rate, shallow breaths that are slowed, thirst, and constipation. There may also be diarrhea in some cases. The eyes begin to sink in and glass over. The muscles begin to become smaller and muscle wasting sets in. Tiredness and dizziness also commonly occur, especially from any physical task. The skin is often overly pale.[13] One prominent sign in children is a swollen belly. Skin loosens and turns pale in color, and there may be swelling of the feet and ankles.
Weakened immune system
Symptoms of starvation may also appear as a weakened immune system, slow wound healing, and poor response to infection. Rashes may develop on the skin. The body directs any nutrients available to keeping organs functioning.
Other symptoms
Other effects of starvation may include:
Buchenwald inmates, 16 April 1945 when camp was liberated
The symptoms of starvation show up in three stages. Phase one and two can show up in anyone that skips meals, diets, and goes through fasting. Phase three is more severe, can be fatal, and results from long-term starvation.
Phase one: When meals are skipped, the body begins to maintain blood sugar levels by degrading glycogen in the liver and breaking down stored fat and protein. The liver can provide glucose for the first few hours. After that, the body begins to break down fat and protein. The body uses fatty acids as an energy source for muscles but lowers the amount of glucose sent to the brain. Another chemical that comes from fatty acids is glycerol. It can be used as glucose for energy but eventually runs out.
Phase two: Phase two can last for weeks at a time. In this phase, the body mainly uses stored fat for energy. The breakdown occurs in the liver and turns fat into ketones. After fasting for one week, the brain will use these ketones and any available glucose. Using ketones lowers the need for glucose, and the body slows the breakdown of proteins.
Phase three: By this point, the fat stores are gone, and the body begins to turn to stored protein for energy. This means it needs to break down muscle tissues full of protein; the muscles break down very quickly. Protein is essential for cells to work correctly, and when it runs out, the cells can no longer function.
The cause of death due to starvation is usually an infection or the result of tissue breakdown. This is due to the body becoming unable to produce enough energy to fight off bacteria and viruses. The final stage of starvation includes signals like hair color loss, skin flaking, swelling in the extremities, and a bloated belly. Even though they may feel hunger, people in the final stage of starvation usually cannot eat enough food to recover without significant medical intervention.
Causes
Starvation occurs when the body expends more energy than it takes in for an extended period of time. This imbalance can arise from one or more medical conditions or circumstantial situations, which can include:
With a typical high-carbohydrate diet, the human body relies on free blood glucose as its primary energy source. Glucose can be obtained directly from dietary sugars and by the breakdown of other carbohydrates. In the absence of dietary sugars and carbohydrates, glucose is obtained from the breakdown of stored glycogen. Glycogen is a readily-accessible storage form of glucose, stored in notable quantities in the liver and skeletal muscle.
After the exhaustion of the glycogen reserve, and for the next two to three days, fatty acids become the principal metabolic fuel. At first, the brain continues to use glucose. If a non-brain tissue is using fatty acids as its metabolic fuel, the use of glucose in the same tissue is switched off. Thus, when fatty acids are being broken down for energy, all of the remaining glucose is made available for use by the brain.[citation needed]
After two or three days of fasting, the liver begins to synthesize ketone bodies from precursors obtained from fatty acid breakdown. The brain uses these ketone bodies as fuel, thus cutting its requirement for glucose. After fasting for three days, the brain gets 30% of its energy from ketone bodies. After four days, this may increase to 70% or more.[16] Thus, the production of ketone bodies cuts the brain's glucose requirement from 80 g per day to 30 g per day, about 35% of normal, with 65% derived from ketone bodies. But of the brain's remaining 30 g requirement, 20 g per day can be produced by the liver from glycerol (itself a product of fat breakdown). This still leaves a deficit of about 10 g of glucose per day that must be supplied from another source; this other source will be the body's own proteins.
After exhaustion of fat stores, the cells in the body begin to break down protein. This releases alanine and lactate produced from pyruvate, which can be converted into glucose by the liver. Since much of human muscle mass is protein, this phenomenon is responsible for the wasting away of muscle mass seen in starvation. However, the body is able to choose which cells will break down protein and which will not. About 2–3 g of protein has to be broken down to synthesize 1 g of glucose; about 20–30 g of protein is broken down each day to make 10 g of glucose to keep the brain alive. However, this number may decrease the longer the fasting period is continued, in order to conserve protein.
Starvation ensues when the fat reserves are completely exhausted and protein is the only fuel source available to the body. Thus, after periods of starvation, the loss of body protein affects the function of important organs, and death results, even if there are still fat reserves left. In a leaner person, the fat reserves are depleted faster, and the protein, sooner, therefore death occurs sooner.[citation needed] Ultimately, the cause of death is in general cardiac arrhythmia or cardiac arrest, brought on by tissue degradation and electrolyte imbalances. Conditions like metabolic acidosis may also kill starving people.[17]
Prevention
Starvation can be caused by factors beyond the control of the individual. The Rome Declaration on World Food Security outlines several policies aimed at increasing food security[18] and, consequently, preventing starvation. These include:
Supporting farmers in areas of food insecurity through such measures as free or subsidized fertilizers and seeds increases food harvest and reduces food prices.[20]
Patients that suffer from starvation can be treated, but this must be done cautiously to avoid refeeding syndrome.[23] Rest and warmth must be provided and maintained. Food can be given gradually in small quantities. The quantity of food can be increased over time. Proteins may be administered intravenously to raise the level of serum proteins.[24] For worse situations, hospice care and opioid medications can be used.
Many organizations have been highly effective at reducing starvation in different regions. Aid agencies give direct assistance to individuals, while political organizations pressure political leaders to enact more macro-scale policies that will reduce famine and provide aid.
According to estimates by the Food and Agriculture Organization, between 720 and 811 million people were affected by hunger globally in 2020.[25] This was a decrease from estimated 925 million in 2010[26] and roughly 1 billion in 2009.[27] In 2007, 923 million people were reported as being undernourished, an increase of 80 million since 1990–92.[28] An estimated 820 million people did not have enough to eat in 2018, up from 811 million in the previous year, which is the third year of increase in a row.[29]
As the definitions of starving and malnourished people are different, the number of starving people is different from that of malnourished. Generally, far fewer people are starving than are malnourished.
The proportion of malnourished and starving people in the world has been more or less continually decreasing for at least several centuries.[30] This is due to an increasing supply of food and to overall gains in economic efficiency. In 40 years, the proportion of malnourished people in the developing world has been more than halved. The proportion of starving people has decreased even faster.
Year
1970
1980
1990
2004
2007
2009
Proportion of undernourished people in the less-developed world[27][31][32]
The starving Livilla refusing food. From a drawing by André Castagne.
Historically, starvation has been used as a death sentence. From the beginning of civilization to the Middle Ages, people were immured, and died for want of food.
In ancient Greco-Roman societies, starvation was sometimes used to dispose of guilty upper-class citizens, especially erring female members of patrician families. In the year 31, Livilla, the niece and daughter-in-law of Tiberius, was discreetly starved to death by her mother for her adulterous relationship with Sejanus and for her complicity in the murder of her own husband, Drusus the Younger.[citation needed]
Another daughter-in-law of Tiberius, named Agrippina the Elder (a granddaughter of Augustus and the mother of Caligula), also died of starvation, in 33 AD; however, it is unclear if her starvation was self-inflicted.
A son and daughter of Agrippina were also executed by starvation for political reasons; Drusus Caesar, her second son, was put in prison in 33 AD, and starved to death by orders of Tiberius (he managed to stay alive for nine days by chewing the stuffing of his bed); Agrippina's youngest daughter, Julia Livilla, was exiled on an island in 41 by her uncle, Emperor Claudius, and her death by starvation was arranged by the empress Messalina.
It is also possible that Vestal Virgins were starved when found guilty of breaking their vows of celibacy.
Ugolino della Gherardesca, his sons, and other members of his family were immured in the Muda, a tower of Pisa, and starved to death in the thirteenth century. Dante, his contemporary, wrote about Gherardesca in his masterpiece The Divine Comedy.
In Sweden in 1317, King Birger of Sweden imprisoned his two brothers for a coup they had staged several years earlier (Nyköping Banquet). According to legend they died of starvation a few weeks later, since their brother had thrown the prison key in the castle moat.
The Makah, a Native American tribe inhabiting the Pacific Northwest near the modern border of Canada and the United States, practiced death by starvation as a punishment for slaves.[33]
The following is a glossary of diabetes which explains terms connected with diabetes.
Ketone bodies are water-soluble molecules or compounds that contain the ketone groups produced from fatty acids by the liver (ketogenesis). Ketone bodies are readily transported into tissues outside the liver, where they are converted into acetyl-CoA – which then enters the citric acid cycle and is oxidized for energy. These liver-derived ketone groups include acetoacetic acid (acetoacetate), beta-hydroxybutyrate, and acetone, a spontaneous breakdown product of acetoacetate.
Ketosis is a metabolic state characterized by elevated levels of ketone bodies in the blood or urine. Physiological ketosis is a normal response to low glucose availability. In physiological ketosis, ketones in the blood are elevated above baseline levels, but the body's acid–base homeostasis is maintained. This contrasts with ketoacidosis, an uncontrolled production of ketones that occurs in pathologic states and causes a metabolic acidosis, which is a medical emergency. Ketoacidosis is most commonly the result of complete insulin deficiency in type 1 diabetes or late-stage type 2 diabetes. Ketone levels can be measured in blood, urine or breath and are generally between 0.5 and 3.0 millimolar (mM) in physiological ketosis, while ketoacidosis may cause blood concentrations greater than 10 mM.
Human nutrition deals with the provision of essential nutrients in food that are necessary to support human life and good health. Poor nutrition is a chronic problem often linked to poverty, food security, or a poor understanding of nutritional requirements. Malnutrition and its consequences are large contributors to deaths, physical deformities, and disabilities worldwide. Good nutrition is necessary for children to grow physically and mentally, and for normal human biological development.
Malnutrition occurs when an organism gets too few or too many nutrients, resulting in health problems. Specifically, it is a deficiency, excess, or imbalance of energy, protein and other nutrients which adversely affects the body's tissues and form.
Ketogenesis is the biochemical process through which organisms produce ketone bodies by breaking down fatty acids and ketogenic amino acids. The process supplies energy to certain organs, particularly the brain, heart and skeletal muscle, under specific scenarios including fasting, caloric restriction, sleep, or others.
Carbohydrate metabolism is the whole of the biochemical processes responsible for the metabolic formation, breakdown, and interconversion of carbohydrates in living organisms.
Famine relief is an organized effort to reduce starvation in a region in which there is famine. A famine is a phenomenon in which a large proportion of the population of a region or country are so undernourished that death by starvation becomes increasingly common. In spite of the much greater technological and economic resources of the modern world, famine still strikes many parts of the world, mostly in the developing nations.
Fatty acid metabolism consists of various metabolic processes involving or closely related to fatty acids, a family of molecules classified within the lipid macronutrient category. These processes can mainly be divided into (1) catabolic processes that generate energy and (2) anabolic processes where they serve as building blocks for other compounds.
Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency is a rare autosomal recessive fatty acid oxidation disorder that prevents the body from converting certain fats into energy. This can become life-threatening, particularly during periods of fasting.
In biochemistry and metabolism, beta oxidation (also β-oxidation) is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA. Acetyl-CoA enters the citric acid cycle, generating NADH and FADH2, which are electron carriers used in the electron transport chain. It is named as such because the beta carbon of the fatty acid chain undergoes oxidation and is converted to a carbonyl group to start the cycle all over again. Beta-oxidation is primarily facilitated by the mitochondrial trifunctional protein, an enzyme complex associated with the inner mitochondrial membrane, although very long chain fatty acids are oxidized in peroxisomes.
Carnitine-acylcarnitine translocase deficiency is a rare, autosomal recessive metabolic disorder that prevents the body from converting long-chain fatty acids into energy, particularly during periods without food. Carnitine, a natural substance acquired mostly through the diet, is used by cells to process fats and produce energy. People with this disorder have a faulty enzyme that prevents long-chain fatty acids from being transported into the innermost part of the mitochondria for processing.
Mitochondrial trifunctional protein deficiency is an autosomal recessive fatty acid oxidation disorder that prevents the body from converting certain fats to energy, particularly during periods without food.
Protein–energy undernutrition (PEU), once called protein-energy malnutrition (PEM), is a form of malnutrition that is defined as a range of conditions arising from coincident lack of dietary protein and/or energy (calories) in varying proportions. The condition has mild, moderate, and severe degrees.
Refeeding syndrome (RFS) is a metabolic disturbance which occurs as a result of reinstitution of nutrition in people who are starved, severely malnourished, or metabolically stressed because of severe illness. When too much food or liquid nutrition supplement is eaten during the initial four to seven days following a malnutrition event, the production of glycogen, fat and protein in cells may cause low serum concentrations of potassium, magnesium and phosphate. The electrolyte imbalance may cause neurologic, pulmonary, cardiac, neuromuscular, and hematologic symptoms—many of which, if severe enough, may result in death.
Starvation response in animals is a set of adaptive biochemical and physiological changes, triggered by lack of food or extreme weight loss, in which the body seeks to conserve energy by reducing metabolic rate and/or non-resting energy expenditure to prolong survival and preserve body fat and lean mass.
The Randle cycle, also known as the glucose fatty-acid cycle, is a metabolic process involving the cross inhibition of glucose and fatty acids for substrates. It is theorized to play a role in explaining type 2 diabetes and insulin resistance.
Catabolysis is a biological process in which the body breaks down fat and muscle tissue in order to stay alive. Catabolysis occurs only when there is no longer any source of protein, carbohydrate, or vitamin nourishment feeding all body systems; it is the most severe type of malnutrition.
A broad classification for genetic disorders that result from an inability of the body to produce or utilize an enzyme or transport protein that is required to oxidize fatty acids. They are an inborn error of lipid metabolism, and when it affects the muscles also a metabolic myopathy.
In medicine, a deficiency is a lack or shortage of a functional entity, by less than normal or necessary supply or function. A person can have chromosomal deficiencies, mental deficiencies, nutritional deficiencies, complement deficiencies, or enzyme deficiencies.
↑ Howe Bancroft, Hubert (1883). "North American states. 1883". History of the Pacific States of North America. 10. A.L. Bancroft,1883: 411.
↑ Taylor, Charles (1811). "The Literary Panorama, Volume 10". The Literary Panorama. 10: 539.
↑ C. J. Coffee (Dec 1, 2004). Quick Look: Metabolism. Hayes Barton Press. p.169.
↑ Toth, HL; Greenbaum, LA (November 2003). "Severe acidosis caused by starvation and stress". American Journal of Kidney Diseases. 42 (5): E16-9. doi:10.1016/j.ajkd.2003.07.012. PMID14582074.
↑ Mulder, Nicholas; van Dijk, Boyd (2021). "Why Did Starvation Not Become the Paradigmatic War Crime in International Law?". Contingency in International Law: On the Possibility of Different Legal Histories. Oxford University Press. pp.370–. ISBN9780192898036.
Wilson, DE; Zeikus, R; Chan, IF (Apr 1987). "Relationship of organ lipoprotein lipase activity and ketonuria to hypertriglyceridemia in starved and streptozocin-induced diabetic rats". Diabetes. 36 (4): 485–90. doi:10.2337/diabetes.36.4.485. PMID3817303.
Swaner, JC; Connor, WE (Aug 1975). "Hypercholesterolemia of total starvation: its mechanism via tissue mobilization of cholesterol". The American Journal of Physiology. 229 (2): 365–9. doi:10.1152/ajplegacy.1975.229.2.365. PMID169705.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
