5 Chapter 5 – Food Safety, Food Security and Population Dynamics

Keep Food Safe! Food Safety Basics[1]

Safe steps in food handling, cooking, and storage are essential in preventing foodborne illness. You can’t see, smell, or taste harmful bacteria that may cause illness. In every step of food preparation, follow the four guidelines to keep food safe:

  • Clean—Wash hands and surfaces often.
  • Separate—Don’t cross-contaminate.
  • Cook—Cook to proper temperatures, checking with a food thermometer.
  • Chill—Refrigerate promptly.

Shopping

  • Purchase refrigerated or frozen items after selecting your non perishables.
  • Never choose meat or poultry in packaging that is torn or leaking.
  • Do not buy food past “Sell-By,” “Use-By,” or other expiration dates.

Storage

  • Always refrigerate perishable food within 2 hours (1 hour when the temperature is above 90 °F).
  • Check the temperature of your refrigerator and freezer with an appliance thermometer. The refrigerator should be at 40 °F or below and the freezer at 0 °F or below.
  • Cook or freeze fresh poultry, fish, ground meats, and variety meats within 2 days; other beef, veal, lamb, or pork, within 3 to 5 days.
  • Perishable food such as meat and poultry should be wrapped securely to maintain quality and to prevent meat juices from getting onto other food.
  • To maintain quality when freezing meat and poultry in its original package, wrap the package again with foil or plastic wrap that is recommended for the freezer.
  • In general, high-acid canned food such as tomatoes, grapefruit, and pineapple can be stored unopened on the shelf for 12 to 18 months. Low-acid canned food such as meat, poultry, fish, and most vegetables will keep 2 to 5 years if the unopened can remains in good condition and has been stored in a cool, clean, and dry place. Discard cans that are dented, leaking, bulging, or rusted.

See our cold storage chart below.

Thawing

  • Refrigerator—The refrigerator allows slow, safe thawing. Make sure thawing meat and poultry juices do not drip onto other food.
  • Cold Water—Place food in a leak-proof plastic bag for faster thawing. Submerge in cold tap water. Change the water every 30 minutes. Cook immediately after thawing.
  • Microwave—Cook meat and poultry immediately after microwave thawing.

Preperation

  • Always wash hands with soap and warm water for 20 seconds before and after handling food.
  • Don’t cross-contaminate. Keep raw meat, poultry, fish, and their juices away from other food. After cutting raw meats, wash cutting board, knife, and counter tops with hot, soapy water.
  • Marinate meat and poultry in a covered dish in the refrigerator.
  • Sanitize cutting boards by using a solution of 1 tablespoon of unscented, liquid chlorine bleach in 1 gallon of water.

Cooking

  • Cook all raw beef, pork, lamb and veal steaks, chops, and roasts to a minimum internal temperature of 145 °F as measured with a food thermometer before removing meat from the heat source. For safety and quality, allow meat to rest for at least three minutes before carving or consuming. For reasons of personal preference, consumers may choose to cook meat at higher temperatures.
  • Ground meats: Cook all raw ground beef, pork, lamb, and veal to an internal temperature of 160 °F as measured with a food thermometer.
  • Poultry: Cook all poultry to an internal temperature of 165 °F as measured with a food thermometer.See our detailed cooking temperature chart below.

Serving

  • Hot food should be held at 140 °F or warmer.
  • Cold food should be held at 40 °F or colder.
  • When serving food at a buffet, keep hot food hot with chafing dishes, slow cookers, and warming trays. Keep cold food cold by nesting dishes in bowls of ice or use small serving trays and replace them often.
  • Use a food thermometer to check hot and cold holding temperatures.
  • Perishable food should not be left out for more than 2 hours at room temperature (1 hour when the temperature is above 90 °F).

Left Overs

  • Discard any food left out at room temperature for more than 2 hours (1 hour if the temperature was above 90 °F).
  • Place food into shallow containers and immediately put in the refrigerator or freezer for rapid cooling.
  • Use most cooked leftovers within 3 to 4 days. (See chart.)
  • Reheat leftovers to 165 °F.

Refreezing

Meat and poultry that has been defrosted in the fridge can be frozen again before or after it has been cooked. If thawed by other methods, cook before refreezing.

Cooking Temperatures

Cooking
Product Type Minimum Internal Temperature & Rest Time
Beef, Pork, Veal & Lamb Ground 160 °F
Steak, chops, and roasts 145 °F and allow to rest for at least 3 minutes
Chicken & Turkey Breasts 165 °F
Ground, stuffing, and casseroles 165 °F
Whole bird, legs, thighs, and wings 165 °F
Eggs Any type 160 °F
Fish & Shellfish Any type 145 °F
Leftovers Any type 165 °F
Ham Fresh or smoked (uncooked) 145 °F and allow to rest for at least 3 minutes
Fully cooked ham (to reheat) Reheat cooked hams packaged in USDA-inspected plants to 140 °F and all others to 165 °F.

Cold Storage Chart

Cold Storage Chart
Preparation Type or Description Refrigerate (40 °F) Freeze (0 °F) *
Beef, Lamb, Pork, Veal
Fresh beef, lamb, veal and pork Ground, hamburger, stew meat, variety meat (tongue, liver, heart, kidney, chitterlings) 1-2 days 3-4 months
Chops, roasts, steaks 3-5 days 4-12 months
Chops, pre-stuffed 1 day Does not freeze well
Leftovers Including casseroles 3-4 days 2-3 months
Corned Beef In pouch, with pickling juices 5-7 days Drained, 1 month
Bacon Bacon 7 days 1 month
Ham (Pre-Cooked)
Fully Cooked Slices 3-4 days 1-2 months
Half 3-5 days 1-2 months
Whole 7 days 1-2 months
Canned Labeled “Keep Refrigerated” Opened 3-5 days 1-2 months
Unopened 6-9 months Do not freeze
Vacuum sealed Unopened, fully cooked vacuum sealed, dated “Use-by” date 1-2 months
Unopened, fully cooked vacuum sealed, undated 2 weeks 1-2 months
Chicken, Turkey, Other Poultry
Fresh Chicken breast, pre-stuffed 1 day Does not freeze well
Ground, patties, giblets 1-2 days 3-4 months
Pieces 1-2 days 9 months
Whole 1-2 days 1 year
Leftovers Casseroles 3-4 days 4-6 months
Chicken nuggets, patties 1-2 days 1-3 months
Pieces, plain or fried 3-4 days 4 months
Pieces in broth or gravy 3-4 days 6 months
Eggs
Fresh In shell 3-5 weeks Do not freeze
Yolk, whites 2-4 days 1 year
Leftovers Casserole, quiche, omelet 3-4 days 2 months
Hard-cooked 1 week Does not freeze well
Opened Liquid pasteurized eggs, egg substitutes 3 days Does not freeze well
Unopened Liquid pasteurized eggs, egg substitutes 10 days 1 year
Sausages, Lunch Meats
Hard Sausage Jerky sticks, pepperoni 2-3 weeks 1-2 months
Raw Sausage Beef, chicken, pork, turkey 1-2 days 1-2 months
Smoked Sausage Breakfast links, patties 7 days 1-2 months
Lunch Meat Deli-sliced or store-prepared 3-5 days 1-2 months
Opened Hot dogs 1 week 1-2 months
Lunch meat—vacuum-packed, sliced 3-5 days 1-2 months
Summer sausage labeled “keep refrigerated” 3 weeks 1-2 months
Unopened Hot dogs 2 weeks 1-2 months
Lunch meat—vacuum-packed, sliced 2 weeks 1-2 months
Summer sausage labeled “keep refrigerated” 3 months 1-2 months
Seafood
Fresh Fish 1-2 days 3-8 months
Shellfish 1-2 days 3-12 months
Leftovers Fish and shellfish 3-4 days 3 months
Miscellaneous
Frozen Dinners and Entrees “Keep frozen” Unsafe to thaw 3-4 months
Mayonnaise Commercial, “refrigerate after opening” 2 months Do not freeze
Other Leftovers Gravy and meat broth 3-4 days 2-3 months
Pizza 3-4 days 1-2 months
Soups and stews 3-4 days 2-3 months
Stuffing 3-4 days 1 month
Salads Egg, chicken, ham, macaroni, tuna (store-prepared, homemade) 3-5 days Does not freeze well

TOP 5 CDC RISK FACTORS

CONTRIBUTING TO FOODBORNE ILLNESS

05.02 Module 05 Discussion Observed Food Handling Violationlink to Blackboard Site

For this discussion, you will discuss food handling violations that you have observed. You will then share your post with your group on a discussion forum. You will return later in the module to reply to the posts of your group peers.

Pre-Discussion Work

To begin this assignment, review the materials in the course textbook under Food Safety

Drafting Your Response

Next, prepare your forum post by creating a Google document. On your document, respond to the following prompt:
  • Write a description of a food handling violation that you have observed within the last 6 months. It can have occurred in your home or in a licensed food establishment. It is not necessary to list the exact establishment, but give a general description such as “a fast food restaurant” or “a full-service restaurant”.
Be sure to support your responses by referencing materials from this module. Also, once you have answered the questions, be sure to proofread what you wrote before you share it.

Discussing Your Work

To discuss your findings, follow the steps below:
Step 01. After you have finished writing and proofreading your response, click on the link to your group under the My Groups link in the main menu on the left side of this page.
Step 02. Once in your group, click on the Group Discussion Board link and locate the Module 03 Discussion Forum 1.
Step 03. In the Module 03 Discussion Forum 1, create a new thread and title it using the following format: Yourname’s Food Handling Violation Post.
Step 04. In the Message field of your post, copy and paste the text of your composition from the Google Document you created– please do not provide a link to that Google Doc.
Step 05. Correct the formatting using the text-editing tools in the Message field. Add bolding, underlining, or italics where necessary. Also, correct any spacing and other formatting issues. Make sure your post looks professional.
Step 06. When you have completed proofreading and fixing your post formatting, click on the Submit button.

 

Did You Know…

There are 48 million people in the United States who get food poisoning each year. As a result, more than 128,000 people are hospitalized, and many people die. The Centers for Disease Control and Prevention (CDC) have identified the top 5 factors contributing to foodborne illnesses:

1)        Improper hot/cold holding temperatures of potentially hazardous foods Up to 90% of all food poisoning cases occur when potentially hazardous foods are not held at proper temperatures. Keep hot foods at 135°F or above and cold foods below 41°F.

2)     Improper cooking temperaturesThe Food and Drug Administration establishes minimum internal temperatures for cooked foods. Temperatures should be measured with a probe thermometer in the thickest part of meats, or the center of other dishes, avoiding bones and container sides.

3)     Contaminated utensils and equipmentContaminated utensils and equipment can lead to cross- contamination of food. In order to prevent the spread of pathogens, all utensils and equipment shall be properly cleaned and sanitized at least once every 4 hours or more frequently as needed.

4)     Poor employee health and hygieneFood workers can be a significant source of harmful microorganisms. Good employee hygiene, such as proper handwashing, is essential to prevent direct and indirect contamination of food, utensils, and other food-related equipment. The person in charge should never allow sick employees to work in the kitchen.

5)        Food from unsafe sourcesAll foods distributed in restaurants and permitted facilities must be obtained from approved sources that comply with applicable laws and regulations.[2]

4 Steps to Food Safety

How do you prevent food poisoning?

Did you know that an estimated 1 in 6 Americans will get sick from food poisoning this year alone? Food poisoning not only sends 128,000 Americans to the hospital each year—it can also cause long-term health problems. You can help keep your family safe from food poisoning at home by following these four simple steps: clean, separate, cook and, chill.

Clean: Wash Hands, Utensils, and Surfaces Often

Germs that can make you sick can survive in many places around your kitchen, including your food, hands, utensils, cutting boards, and countertops.

Wash your hands the right way:

  • Use plain soap and water—skip the antibacterial soap—and scrub the backs of your hands, between your fingers, and under your nails for at least 20 seconds. Need a timer? Hum the “Happy Birthday” song from beginning to end twice.
  • Rinse hands, then dry with a clean towel.
  • Wash your hands often, especially during these key times when germs can spread:
    • Beforeduring, and after preparing food
    • After handling raw meat, poultry, seafood, or their juices, or uncooked eggs
    • Before eating
    • After using the toilet
    • After changing diapers or cleaning up a child who has used the toilet
    • After touching an animal, animal feed, or animal waste
    • After touching garbage
    • Before and after caring for someone who is sick
    • Before and after treating a cut or wound
    • After blowing your nose, coughing, or sneezing
    • After handling pet food or pet treats.

Wash surfaces and utensils after each use:

  • Wash cutting boards, dishes, utensils, and countertops with hot, soapy water, especially after they’ve held raw meat, poultry, seafood, or eggs.
  • Wash dish cloths often in the hot cycle of your washing machine.

Wash fruits and vegetables, but not meat, poultry, or eggs:

  • Rinse fruits and vegetables under running water without soap, bleach, or commercial produce washes.
  • Rinse fruits and vegetables before peeling, removing skin, or cutting away any damaged or bruised areas.
  • Scrub firm produce like melons or cucumbers with a clean produce brush.
  • Dry produce with a paper towel or clean cloth towel.
  • Don’t wash meat, poultry, eggs, or seafood to avoid spreading harmful germs around your kitchen.
  • Produce labeled as “pre-washed” does not need to be washed again.

Separate: Don’t Cross Contaminate

Use separate cutting boards and plates for produce, meat, poultry, seafood, and eggs:

  • Use one cutting board for fresh produce or other foods that won’t be cooked before they’re eaten, and another for raw meat, poultry, or seafood. Replace them when they are worn.
  • Use separate plates and utensils for cooked and raw foods.
  • Use hot, soapy water to thoroughly wash plates, utensils, and cutting boards that touched raw meat, poultry, seafood, eggs, or flour.

Keep certain types of food separate:

  • In your shopping cart, separate raw meat, poultry, seafood, and eggs from other foods and place packages of raw meat, poultry, and seafood in plastic bags if available. When you check out, place raw meat, poultry, and seafood in separate bags from other foods.
  • At home, place raw meat, poultry, and seafood in containers or sealed, leakproof plastic bags. Freeze them if you’re not planning to use them within a few days.
  • In the fridge, keep eggs in their original carton and store them in the main compartment—not in the door.

Cook to the Right Temperature

Food is safely cooked when the internal temperature is high enough to kill germs that can make you sick:

  • Use a food thermometer to be sure your food is safe. When you think your food is done, place the food thermometer in the thickest part of the food, making sure not to touch bone, fat, or gristle.
  • Refer to our Minimum Cooking Temperatures Chart to be sure your foods have reached a safe temperature.

Keep food hot (140˚F or above) after cooking:

If you’re not serving food right after cooking, keep it out of the temperature danger zone (between 40°F -140°F) where germs grow rapidly by using a heat source like a chafing dish, warming tray, or slow cooker.

Microwave food thoroughly (165˚F or above):

  • Read package directions for cooking and follow them exactly to make sure food is thoroughly cooked.
  • If the food label says, “Let stand for x minutes after cooking,” follow the directions — letting microwaved food sit for a few minutes allows food to cook thoroughly as colder areas absorb heat from hotter areas.
  • Stir food in the middle of heating. Follow package directions for commercially prepared frozen food; some are not designed to be stirred while heating.

Chill: Refrigerate and Freeze Food Properly

Refrigerate perishable foods within 2 hours:

  • Bacteria that cause food poisoning multiply quickest between 40°F and 140°F.
  • Your refrigerator should be set to 40°F or below and your freezer to 0°F or below. Use an appliance thermometer to be sure.
  • Never leave perishable foods out of refrigeration for more than 2 hours. If the food is exposed to temperatures above 90°F (like a hot car or summer picnic), refrigerate it within 1 hour.
  • Leftovers should be placed in shallow containers and refrigerated promptly to allow quick cooling.
  • Never thaw or marinate foods on the counter. The safest way to thaw or marinate meat, poultry, and seafood is in the refrigerator.
  • Freezing does not destroy harmful germs, but it does keep food safe until you can cook it.
  • Know when to throw out food by checking our Safe Storage Times chart. Be sure you throw food out before harmful bacteria grow.

Food Safety by Type of Food

Some foods are more frequently associated with food poisoning or foodborne illness than others. It is especially important to handle these foods properly. Use these tips and techniques to help keep food safe and prevent food poisoning.

Meat Raw meat may contain parasites and bacteria such as E. coli and Salmonella. Thorough cooking destroys these harmful germs, but meat can become contaminated again if it is not handled and stored properly. For information about meat preparation, see these fact sheets.
Poultry Raw poultry may contain harmful bacteria such as Salmonella and Campylobacter. Never wash raw poultry. Cook chicken to the proper temperature to kill germs. For information about poultry preparation, see these fact sheets. For information about handling turkey safely, see these fact sheets.
Seafood A well-balanced diet that includes a variety of fish and shellfish can contribute to heart health and children’s growth and development. But raw seafood can contain toxins such as mercury or bacteria that can be destroyed only by cooking to the proper temperature. Learn more about selecting, preparing, and serving seafood safely.
Eggs and egg products Eggs are one of nature’s most nutritious and economical foods, but fresh eggs must be handled carefully. Even eggs with clean, uncracked shells may occasionally contain Salmonella. To prevent food poisoning, keep eggs refrigerated, cook eggs until yolks are firm, and cook foods containing eggs thoroughly.
Milk, cheese, and dairy products You can get very sick from raw milk and from dairy products made with raw milk, including soft cheeses such as queso fresco and brie, as well as ice cream and yogurt. That’s why it’s important to make sure that milk has been pasteurized, which kills harmful bacteria. Learn why raw milk is risky.
Fresh fruits, vegetables, and juices Fresh produce can pick up harmful bacteria from many sources, from contaminated soil and water to a contaminated cutting board. Fruit and vegetable juices must be treated to kill bacteria. Learn more about selecting and serving produce safely.
Nuts, grains, and beans Nuts, grains, beans, and other legumes and their by-products are found in a wide variety of foods. Since these foods are ingredients in so many food products, contamination or mislabeling of allergens can pose a widespread risk. Learn more from the FDA about food allergens and what to do if symptoms occur. Also, people suffering from celiac disease—for whom consuming the gluten naturally found in some grains can lead to such serious conditions as anemia, osteoporosis, diabetes, thyroid disease, and intestinal cancers—should see FDA’s Gluten and Food Labeling.
Raw flour Flour is typically a raw agricultural product that hasn’t been treated to kill germs. Bacteria are killed when food made with flour is cooked. That’s why you should never taste raw dough or batter.
Baby food and infant formula Infants and young children are more likely to get a foodborne illness because their immune systems are not developed enough to fight off infections. Take extra care when handling and preparing their food and formula.
Pet food Pet food can contain harmful bacteria or chemical toxins. If pet food is not handled properly, both pets and people could get sick. Keep infants and young children away from areas where you feed your pets, and never allow them to touch or eat pet food. Learn more about safely handling pet food and treats.

 

Parties and Large Groups

Infographic from FoodSafety.gov with tips for safely cooking food for parties and large groups.

When food for parties and large groups is prepared in different locations by different people, how can you make sure that everyone prepares and stores food safely? Consult these guidelines:

Bag Lunches for School and Work

Infographic from FoodSafety.gov with back-to-school food safety tips and steps for preparing safe school lunches.

Bacteria that cause food poisoning grow rapidly at temperatures between 40 °F and 140°F. To make sure perishable lunches and snacks are safe, pack them with two cold sources. Store them in a refrigerator or cooler on arrival, if one is available.

Summer and Vacation

Infographic from FoodSafety.gov with tips for a food-safe summer and safely preparing signature summer dishes.

Foodborne illnesses tend to increase during the summer months because bacteria multiply faster when it’s warm. People also cook outside, away from refrigerators, thermometers, and sinks more often. Stay healthy and safe by following these food safety guidelines:

Thanksgiving

Infographic from FoodSafety.gov with tips for handling and cooking turkey and keeping your Thanksgiving safe and delicious.

The Thanksgiving meal is the largest that many cooks prepare each year. The following information may help you prepare your special Thanksgiving meal and help you countdown to the holiday.

Weddings

This infographic shares tips on how to plan a safe wedding menu and avoid potential food allergens.

When planning the perfect wedding menu, you can’t afford to forget food safety. From the engagement party to the honeymoon, remember these food safety to-do’s before saying your “I Do’s”. Whether catering or DIY, learn how to keep your guests safe.[3]

Food Security

English economist Malthus is best known for his hugely influential theories on population growth.

Thomas Robert Malthus was born near Guildford, Surrey in February 1766. His father was prosperous but unconventional and educated his son at home. Malthus went on to Cambridge University, earning a master’s degree in 1791. In 1793, he was made a fellow of Jesus College, Cambridge. In 1805, Malthus became professor of history and political economy (the first holder of such an academic office) at the East India Company’s college in Haileybury, Hertfordshire, where he remained until his death.

In 1819, Malthus was elected a fellow of the Royal Society and two years later he became a member of the Political Economy Club, whose members included David Ricardo and James Mill. In 1824, he was elected as one of the 10 royal associates of the Royal Society of Literature. Malthus was also one of the co-founders of the Statistical Society of London in 1834.

Malthus’ most well known work ‘An Essay on the Principle of Population’ was published in 1798, although he was the author of many pamphlets and other longer tracts including ‘An Inquiry into the Nature and Progress of Rent’ (1815) and ‘Principles of Political Economy’ (1820). The main tenets of his argument were radically opposed to current thinking at the time. He argued that increases in population would eventually diminish the ability of the world to feed itself and based this conclusion on the thesis that populations expand in such a way as to overtake the development of sufficient land for crops. Associated with Darwin, whose theory of natural selection was influenced by Malthus’ analysis of population growth, Malthus was often misinterpreted, but his views became popular again in the 20th century with the advent of Keynesian economics.

Malthus died on 23 December 1834.[4]

 

Both graphs (a) and (b) plot population size versus time. In graph (a), exponential growth results in a curve that gets increasingly steep, resulting in a J-shape. In graph (b), logistic growth results in a curve that gets increasingly steep, then levels off when the carrying capacity is reached, resulting in an S-shape
Figure 1: When resources are unlimited, populations exhibit exponential growth, resulting in a J-shaped curve. When resources are limited, populations exhibit logistic growth. In logistic growth, population expansion decreases as resources become scarce, and it levels off when the carrying capacity of the environment is reached, resulting in an S-shaped curve. (credit: “population growth” by OpenStax is licensed under CC BY 4.0)[5]

Current World Population [website]. Worldometers.

  • View this world population meter website that shows the increase in population in real time.
  • Be sure to scroll down the page and view the 20 largest countries by population and related charts and figures. You should also look at other charts and facts below the meter.
World Population
In demographics, the world population is the total number of humans currently living. It was estimated by the United Nations to have exceeded 8 billion in November 2022. It took over 200,000 years of human prehistory and history for the human population to reach one billion and only 219 years more to reach 8 billion. The human population experienced continuous growth following the Great Famine of 1315–1317 and the end of the Black Death in 1350, when it was nearly 370,000,000. The highest global population growth rates, with increases of over 1.8% per year, occurred between 1955 and 1975, peaking at 2.1% between 1965 and 1970. The growth rate declined to 1.1% between 2015 and 2020 and is projected to decline further in the 21st century. The global population is still increasing, but there is significant uncertainty about its long-term trajectory due to changing fertility and mortality rates.[6]

What Happens When We Starve? Phases of Starvation

Published: 2016-02-01 – Updated: 2020-12-02
Author: Thomas C. Weiss | Contact: Disabled World (www.disabled-world.com)
Peer-Reviewed Publication: N/A
Additional References: Library of Fitness and Nutrition Publications

 

Synopsis: Information regarding the stages of starvation and the effect malnutrition has on the human body. After approximately a week of fasting, a person’s brain starts to use ketone bodies, as well as glucose, for sources of energy. Proteins not essential for survival are used first. The third phase of starvation starts when a person’s fat reserves are depleted and there is a switch to proteins as the major source of the person’s energy.

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Main Digest

 

A person’s body can go without oxygen for approximately five to ten minutes and around three to eight days without water. Yet remarkably, people have been known to live for more than seventy days without food. The question that arises is, ‘How can this be?’

The answer to this question lies in a series of evolved physiological and metabolic defenses that work to keep a person alive for as long as possible in the event they do not have access to food. Just because a person is starving does not mean they have become helpless. What follows is an explanation of how a person’s body fights to keep them alive and active.

Defining the Word “Starvation”

Starvation is defined as a severe deficiency in caloric energy intake needed to maintain human life. It is the most extreme form of malnutrition. In humans, prolonged starvation can cause permanent organ damage and eventually, death. The basic cause of starvation is an imbalance between energy intake and energy expenditure. The term inanition refers to the symptoms and effects of starvation. Starvation can be caused by factors, other than illness, outside of the control of the individual.

By its very definition, starvation is a process. Our bodies are not like vehicles which promptly shut down when they are out of gasoline. When we experience prolonged low-energy intake and as long as water is available, our bodies enter into a series of metabolic modes. It is the body’s way of recognizing that food is scarce and that it needs to re-allocate resources in preparation for what might be an extended period of time. Basically, a person’s body is buying them some time to give them a chance to find some food.

Starvation results from the inadequate intake of nutrients or the inability to metabolize or absorb nutrients. It may have several causes such as:

  • Disease
  • Anorexia
  • Deprivation
  • Prolonged fasting

Despite the cause, starvation takes about the same course and consists of three phases. The events of the first two phases happen even during fairly short periods of dieting or fasting. The third phase happens only in prolonged starvation and may end in the person’s death.

The First Phase of Starvation

During the first stage of starvation, blood glucose levels are maintained through the production of glucose from proteins, glycogen and fats.

At first, glycogen is broken down into glucose. Only enough glycogen; however, is stored in the person’s liver to last a few hours. After that period of time, blood glucose levels are maintained by the breakdown of fats and proteins.

Fats are decomposed into glycerol and fatty acids. Fatty acids can be used as a source of energy, particularly by skeletal muscle, thereby decreasing the use of glucose by tissues other than the brain.

Glycerol may be used to make a small amount of glucose, yet most of the glucose is formed from the amino acids of proteins. Some amino acids might be used directly for energy.

The Second Phase of Starvation

In the second phase, which might last for several weeks, fats are the main energy source.

A person’s liver metabolizes fatty acids into ketone bodies that can be used as a source of energy.

After approximately a week of fasting, a person’s brain starts to use ketone bodies, as well as glucose, for sources of energy. Proteins not essential for survival are used first.

The Third Phase of Starvation

The third phase of starvation starts when a person’s fat reserves are depleted and there is a switch to proteins as the major source of the person’s energy. Muscles, the largest source of protein in the body, are quickly depleted. At the end of this phase, proteins – essential for cellular functions, are broken down and cell function degenerates. Along with loss of weight, symptoms of starvation include:

  • Apathy
  • Withdrawal
  • Listlessness
  • Increased susceptibility to disease

Additional signs of starvation may include flaky skin, changes in hair color and massive edema in the lower limbs and abdomen, causing the person’s abdomen to seem bloated. During the process of starvation, the ability of the human body to consume volumes of food also decreases.

Foods low in protein yet high in bulk often times cannot reverse the process of starvation. Intervention involves feeding the affected person low-bulk food that provides lots of proteins and kilo-calories and is fortified with minerals and vitamins.

The process of starvation also results in dehydration and dehydration is an important part of intervention. Even with intervention, a person might be so affected by weakness or disease they do not have the ability to make a recovery.

Starvation and Death

Few people die directly from starvation because they usually die of an infectious disease first.

Starvation wreaks havoc on a person’s immune system, largely on account of an extreme deficiency of minerals and vitamins. Some people will become weak and perish of immune-related diseases during starvation. Eventually, the person’s body will run out of options. Fats, glucose, muscle mass and tissue are finite resources that will eventually be spent and the person will die. The end-stage of starvation usually brings with it one of two different diseases – kwashiorkor and marasmus.

Marasmus happens due to extreme energy deficiency, often from inadequate amounts of calories and protein. The person’s body weight reaches dangerously low levels and infections are common. Kwashiorkor is a related disease that affects children who are protein-energy deficient and might result in edema and an enlarged and fatty liver, resulting in the distending of the children’s bellies, providing the illusion that children who are starving are well-fed.

When the person’s death finally arrives, its most immediate cause is by cardiac arrhythmia or a heart attack brought on by either extreme tissue degradation brought about by autophagy, or severe electrolyte imbalances. People can die of starvation in as little as three-weeks, or as long as seventy days.[7]

 

Malnutrition[8]

Key facts

  • Malnutrition, in all its forms, includes undernutrition (wasting, stunting, underweight), inadequate vitamins or minerals, overweight, obesity, and resulting diet-related noncommunicable diseases.
  • 1.9 billion adults are overweight or obese, while 462 million are underweight.
  • Globally in 2020, 149 million children under 5 were estimated to be stunted (too short for age), 45 million were estimated to be wasted (too thin for height), and 38.9 million were overweight or obese.
  • Around 45% of deaths among children under 5 years of age are linked to undernutrition. These mostly occur in low- and middle-income countries. At the same time, in these same countries, rates of childhood overweight and obesity are rising.
  • The developmental, economic, social, and medical impacts of the global burden of malnutrition are serious and lasting, for individuals and their families, for communities and for countries.

Malnutrition refers to deficiencies, excesses, or imbalances in a person’s intake of energy and/or nutrients. The term malnutrition addresses 3 broad groups of conditions:

  • undernutrition, which includes wasting (low weight-for-height), stunting (low height-for-age) and underweight (low weight-for-age);
  • micronutrient-related malnutrition, which includes micronutrient deficiencies (a lack of important vitamins and minerals) or micronutrient excess; and
  • overweight, obesity and diet-related noncommunicable diseases (such as heart disease, stroke, diabetes and some cancers).

Various forms of malnutrition

Undernutrition

There are 4 broad sub-forms of undernutrition: wasting, stunting, underweight, and deficiencies in vitamins and minerals. Undernutrition makes children in particular much more vulnerable to disease and death.

Low weight-for-height is known as wasting. It usually indicates recent and severe weight loss, because a person has not had enough food to eat and/or they have had an infectious disease, such as diarrhoea, which has caused them to lose weight. A young child who is moderately or severely wasted has an increased risk of death, but treatment is possible.

Low height-for-age is known as stunting. It is the result of chronic or recurrent undernutrition, usually associated with poor socioeconomic conditions, poor maternal health and nutrition, frequent illness, and/or inappropriate infant and young child feeding and care in early life. Stunting holds children back from reaching their physical and cognitive potential.

Children with low weight-for-age are known as underweight. A child who is underweight may be stunted, wasted, or both.

Micronutrient-related malnutrition

Inadequacies in intake of vitamins and minerals often referred to as micronutrients, can also be grouped together. Micronutrients enable the body to produce enzymes, hormones, and other substances that are essential for proper growth and development.

Iodine, vitamin A, and iron are the most important in global public health terms; their deficiency represents a major threat to the health and development of populations worldwide, particularly children and pregnant women in low-income countries.

Overweight and obesity

Overweight and obesity is when a person is too heavy for his or her height. Abnormal or excessive fat accumulation can impair health.

Body mass index (BMI) is an index of weight-for-height commonly used to classify overweight and obesity. It is defined as a person’s weight in kilograms divided by the square of his/her height in meters (kg/m²). In adults, overweight is defined as a BMI of 25 or more, whereas obesity is a BMI of 30 or more.

Overweight and obesity result from an imbalance between energy consumed (too much) and energy expended (too little). Globally, people are consuming foods and drinks that are more energy-dense (high in sugars and fats), and engaging in less physical activity.

Diet-related noncommunicable diseases

Diet-related noncommunicable diseases (NCDs) include cardiovascular diseases (such as heart attacks and stroke, and often linked with high blood pressure), certain cancers, and diabetes. Unhealthy diets and poor nutrition are among the top risk factors for these diseases globally.

Scope of the problem

In 2014, approximately 462 million adults worldwide were underweight, while 1.9 billion were either overweight or obese.

In 2016, an estimated 155 million children under the age of 5 years were suffering from stunting, while 41 million were overweight or obese.

Around 45% of deaths among children under 5 years of age are linked to undernutrition. These mostly occur in low- and middle-income countries. At the same time, in these same countries, rates of childhood overweight and obesity are rising.

Who is at risk?

Every country in the world is affected by one or more forms of malnutrition. Combating malnutrition in all its forms is one of the greatest global health challenges.

Women, infants, children, and adolescents are at particular risk of malnutrition. Optimizing nutrition early in life—including the 1000 days from conception to a child’s second birthday—ensures the best possible start in life, with long-term benefits.

Poverty amplifies the risk of, and risks from, malnutrition. People who are poor are more likely to be affected by different forms of malnutrition. Also, malnutrition increases health care costs, reduces productivity, and slows economic growth, which can perpetuate a cycle of poverty and ill-health.

 


  1. https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/steps-keep-food-safe
  2. https://wp.sbcounty.gov/dph/programs/ehs/food-handlers-managers/
  3. https://www.foodsafety.gov/keep-food-safe/food-safety-by-events-and-seasons
  4. https://www.bbc.co.uk/history/historic_figures/malthus_thomas.shtml
  5. https://openoregon.pressbooks.pub/mhccmajorsbio/chapter/environmental-limits-to-population-growth/
  6. https://en.wikipedia.org/wiki/World_population
  7. https://www.disabled-world.com/fitness/starving.php
  8. https://www.who.int/news-room/fact-sheets/detail/malnutrition

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