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Varied diet -

Food consumption is essential to human life. Eating a balanced and varied diet can benefit our health by reducing risks associated with malnutrition.

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Water -

Water, too, is vital for life. In fact, there can be no life on Earth without water. Recommended daily intake of fluid is about 15.5 cups (3.7 liters) of fluids a day for men, and approximately 11.5 cups (2.7 liters) of fluids a day for women, according to the US National Academies of Sciences, Engineering, and Medicine.

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Eating and drinking -

Our bodies require energy from food sources and hydration from water to function properly. When we don't eat enough food, the body begins to increase production of cortisol, leaving us stressed and hungry.

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Dehydration -

Not drinking enough water can cause dehydration. Low water intake is also responsible for a host of other ailments, including fatigue, headache, weakened immunity, and dry skin.

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Lack of fluids -

The effects of dehydration can quickly turn serious and even life-threatening. In fact, the human body can only function without water for around four days before closing down.

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Absence of food -

Researchers agree, however, that a person can live up to three weeks without food as long as they have enough water to drink. But the absence of food in the system begins to have negative consequences on the body sooner than you think.

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Significant consequences -

Skipping a meal now and again has a negligible effect on the body. But neglecting to eat over a prolonged period can have significant consequences on your brain and your body.

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Food for fuel -

Food is fuel. The protein, carbohydrates, good fats, vitamins, and minerals that make up the nutrients in food supply us with energy. If you neglect to fuel up for whatever reason, you're basically running on empty.  

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Low blood sugar -

One of the first symptoms of malnutrition is low blood sugar. Glucose fuels the brain, which is supplied by foods rich in carbohydrates. Low blood sugar can zap your energy, making you feel lethargic and weak.

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Hunger pangs -

Stomach growling is commonly heard and associated with hunger and an absence of food in the stomach. This uncomfortable sensation is also called a hunger pang, caused by strong contractions of the stomach when it's empty.

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Starvation sets in -

Eliminating food and water intake for a significant period of time is known as starvation. But the length in which you can survive without food depends of a variety of factors.

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Food for thought -

Besides impacting the physical state, the initial stages of starvation also affect mental status and behaviors. An irritable mood, fatigue, and trouble concentrating are typical indicators. So, too, is a preoccupation of food thoughts.

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How long can you survive? -

How long you can survive without food also depends on your overall health, your sex, body composition, your environment, and, of course, what you last ate and drank.

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Longer life expectancy -

According to World Data, average life expectancy of women in the US is 81.4 years. For men, it's 76.3. Furthermore, on average, women can also expect a longer life expectancy when facing the harshest conditions—including famines and epidemics. Women therefore tend to have a greater survival advantage when faced with starvation.

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Using fat reserves -

People with more fat reserves may survive longer, since the body can burn stored fat for fuel in times of extreme hunger.

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Breakdown of protein -

Inevitably as starvation sets in, the physical symptoms become more severe. While considerable amounts of body fat may be lost during starvation, the main danger comes from the breakdown of protein.

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Muscle wastage -

Visually, the most apparent sign of starvation is muscle wasting. This ominous feature points to the parallel loss of functional proteins in the heart, liver, kidneys, and other tissues.

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Undernourished -

Being undernourished is how starvation begins, when people don't get enough calories to keep up with the body's energy needs. Indeed, it only takes about eight hours without eating for your body to change how it operates.

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Disease sets in -

Over weeks and months as starvation progresses, malnutrition can result in specific diseases like anemia, when the body doesn't get enough iron, or beriberi due to inadequate thiamine.

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Lower metabolism -

Bereft of nourishment, the body begins to feed on itself. Fat reserves are depleted and the metabolism slows. The body can't regulate its own temperature.

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Impaired kidney function -

With nothing to eat, kidney function is impaired, heart rate quickens, and breathing—by now already shallow—slows. The immune system weakens.

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When fat stores deplete -

When fat stores are gone, the body begins to turn to stored protein for energy. This results in muscle loss. In fact, there's nothing left for the body to scavenge except muscle.

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Effect on the heart -

Bear in mind that the heart is a muscle and the primary organ of your circulatory system. At this late stage it is functioning poorly, making breathing even more of a struggle.

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Skeletal appearance -

With muscle literally eaten away and tissue broken down, there's little left of the human body except for skin and bone. Starvation has left a skeletal appearance.

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Final stages -

In the final stages of starvation, people can experience hallucinations and convulsions. Other signals may include hair loss, skin rupture, and a bloated belly (incidentally a prominent sign in severely undernourished children).

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Death -

With the body severely weakened and unable to produce enough energy to fight off bacteria and viruses, the heart finally stops beating.

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World hunger -

According to the World Health Organization, more than 820 million people are hungry globally. This underscores the immense challenge of achieving the Sustainable Development Goal of Zero Hunger by 2030, which the Geneva-based agency is committed to achieving.

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What causes hunger? -

Global humanitarian organization Action Against Hunger lists poverty, conflict, gender equality, seasonal changes, natural disasters, and lack of access to safe drinking water as the underlying factors of malnutrition.

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Famine relief -

But it is conflict that is the biggest driver of famine, according to the World Food Programme (WFP). For its efforts, the WFP was awarded the Nobel Peace Prize in 2020 for its endeavors in providing food assistance in areas of conflict, and preventing the use of food as a weapon of war. 

Sources: (American University Radio) (National Academies) (Scientific American) (World Data) (WHO) (Action Against Hunger) (World Food Programme)

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