- Nutrition is a critical part of our health and development.
- There are three types of nutrition in this world: autotrophic, heterotrophic and mixotrophic nutrition.
- We need different elements of nutrition daily to live and function.
Can you live without food?
Because food gives us all the nutrients that we need to live.
And the way we eat food and use it, is called nutrition.
Without nutrition, we cannot get food and there will be no life on this planet.
So, nutrition is a life process, without which we cannot survive.
In this article, I will discuss everything about nutrition.
So, let’s dive in. 🧐
Table of Contents
- Key Highlights
- What is Nutrition?
- History of Nutrition
- Facts about Nutrition
- Importance of Nutrition
- Nutrition Goals/Purpose/Function
- Types of Nutrition
- Elements of Nutrition
- Stages of Human Nutrition
- The Final Word
- FAQs about Nutrition
What is Nutrition?
Different health organizations have different definitions of nutrition. But the meanings are the same. For example,
According to WHO, nutrition is a critical part of our health and development. 
According to MedicineNet, nutrition is the process of taking food for growth, metabolism, and repair. 
Let me give you my definition of nutrition. 🤩
Nutrition is a biological process of consuming foods to fulfill the dietary needs of our body.
Let me elaborate a little bit. 🧐
Our microscopic cells need even smaller components to live and perform their function. Most of these components come from the food we eat.
The process we use to get those components from food is called nutrition.
Sometimes nutrition can be defined in terms of education. 📖
In terms of education, nutrition refers to studying the relationship between food and health (diseases) to seek the well-being and preservation of human health. 
Summary: According to NutritionCrown, nutrition is a biological process of consuming foods to fulfill the dietary needs of our body.
History of Nutrition
Since the appearance of humans on earth, the type of food has varied over time.
Because we are always forced to adapt to the easiest and closest available food.
Did you know some evidence says that early humans were scavengers and practiced cannibalism? 
They were also competing for their food with other animals of similar eating habits.
Let me give you a brief idea about nutrition history. 🧐
Before 2.6 million years ago, our earth was cooler and most of the earth surface was covered with ice.
At that time our distant human ancestors, collectively known as hominins, were mostly dependent on plant-based foods for survival. 
But as the earth temperature rose, the forest shrank and great grasslands thrived. 🌳
At that time, plant foods became rare and different herbivores animals were growing.
This evolutionary pressure forced early humans to find new food sources.
They started eating meat and marrow from small to very large animals even from fallen carcasses. Because at that time our ancient hominin ancestors weren’t capable of hunting. 
But with time they learn how to hunt and start eating fresh meat regularly.
Evidence suggests that meat is the food that makes our brain so big and powerful and makes us human. 
The goals of life for our ancestors were very different from ours. Their goal was to survive to the next day.
But in today’s world, we still eat meat, because we like it and for our cultural significance; not because we need it. 
The diet of the early modern humans varied significantly depending on the locality and the climate.
The diet in the tropics tends to be based preferentially on plant foods, while the diet in the high latitudes tends more towards animal products. 🍲
Agriculture developed about 10,000 years ago in multiple locations throughout the world, providing grains such as wheat, rice and corn along with staples such as bread and pasta.
About 12,000 years ago, the first agricultural revolution began and we got a new fixed source of protein.
Agriculture provides us with a variety of vegetables and grains as well as staple foods like bread and pasta.
It also gave us milk, milk products, meat and meat products.
The importance of food purity was recognized when mass storage of food led to contamination.
Modern cooking was often developed as a ritualistic activity.
It requires strict recipes and procedures in response to the demand for purity and consistency in food.
Let me give you the important timelines of nutrition science. 🕒
Note: There was lots of research done in the past, but I have included the important and major incidents.
475 BC: Anaxagoras, a Pre-Socratic Greek philosopher, declares that in order for the food an animal eats to turn into bone, hair, flesh, and so forth, it must already contain all of those constituents within the food. 
400 BC: Hippocrates, a Greek physician, says “Let food be thy medicine, and let medicine be thy food.” Although a recent study says it is a widespread misquotation. 
1500: Leonardo da Vinci, an artist and scientist, compares metabolism to a burning candle. 
1614: Santorio Santorio, an Italian physiologist, describes how a part of the food is lost during digestion. 
1747: Dr. James Lind, a British Navy physician conducts the first scientific experiment in nutrition and finds that lemon juice saves sailors who have been at sea for years suffering from scurvy (a deadly and painful bleeding disorder). 
1770: Antoine Lavoisier, a prominent French chemist and the Father of Nutrition and Chemistry, discovered the concept of metabolism. He also showed that the oxidation of food is the source of body heat. 
1816: François Magendie, a French physiologist, declared that protein is an essential component of the diet. 
1840: Justus von Liebig, a German chemist, discovered the role of carbohydrates (sugars), fats (fatty acids) and proteins (amino acids) in nutrition. 
1860: Claude Bernard, a French physiologist, discovered that body fat can be synthesized from carbohydrates and proteins. He also proved that the energy in blood glucose can be stored as fat or glycogen. 
1985: Kanehiro Takaki, a Japanese naval medical officer, shows that adding milk and meat to the Japanese diet prevented beriberi. 
1896: Eugen Baumann, a German chemist, observed iodine in the thyroid gland. 
1897: Christiaan Eijkman, a Dutch physician and pathologist, found that feeding chickens either unpolished rice or the discarded rice polishings can cure beriberi. 
1906: Wilcock and Hopkins show that the amino acid tryptophan is necessary for mouse survival. 
1912: Casimir Funk, a Polish biochemist and ‘father of vitamin therapy’, coined the term “vitamin” from the word “vital” (because these unknown substances prevented scurvy, beriberi and pellagra) and from the suffix “amino”, thinking that they were derived from ammonia. 
1913: American researchers Elmer McCollum and Marguerite Davis in 1914 discovered a substance in cod liver oil which later was called “vitamin A”. In 1952, TIME magazine called him Dr. Vitamin. 
1915: McCollum also helped discover vitamin B and vitamin D and worked out the effect of trace elements in the diet. 
1918: McCollum, an American researcher, said that milk was the greatest of all protective food. After this statement, the milk consumption in the United States doubled between 1918 and 1928. He also promoted leafy greens, which had no industry advocates. 
1920: Sir Edward Mellanby, a British researcher, incorrectly identifies rickets as a vitamin A deficiency, because he manages to cure it in dogs with cod liver oil. 
1922: McCollum shows that vitamin A in cod liver oil can be destroyed by heating. However, he discovered that it still cured rickets, leading to the discovery of heat-stable vitamin D. 
1922: American scientists, HM Evans and LS Bishop discovered vitamin E as an essential factor for rat pregnancy, calling it food factor X, until 1924. 
1926: Barend Jansen and Willem Donath, Dutch chemist and biochemist, crystallized thiamine or vitamin B1 (They named it aneurin, for antineuritic vitamin). 
1927: Adolf Windaus, a German chemist, was able to synthesize vitamin D, for which he won the Nobel Prize in chemistry in 1928. 
1928: Albert Szent-Györgyi, a Hungarian biochemist, was able to isolate ascorbic acid, and in 1932 he proved that vitamin C can prevent scurvy. In 1935 he synthesized it and in 1937 he won the Nobel Prize for his efforts. At that time Szent-Gyorgyi also explained the citric acid cycle. 
1930: William Cumming Rose, an American biochemist and nutritionist, discovered the amino acid threonine. His research determined the importance for essential amino acids in diet and the minimum daily requirements of all amino acids for optimal growth. 
1935: Robert R. Williams, an American chemist, reported the chemical composition and synthesized thiamine or vitamin B1. He also coined the name for it, thiamin. 
1936: Eugene Floyd Dubois, an American physician, showed that the performance at work and school are related to the person’s caloric intake. 
1938: The chemical structure of vitamin E is discovered by Erhard Fernholz and is synthesized by Paul Karrer. 
1941: The first Recommended Dietary Allowances were established by the National Research Council. 
1992: The United States Department of Agriculture introduces the food pyramid. 
In the 20th century, many vitamins were discovered and isolated and the concept of supplementing health with vitamins was born.
The first vitamin pills were marketed in the 1930s, and created a new industry around science-based health products. 💊
In October 1994, the Dietary and Supplement Health and Education Act was approved by Congress. 
It defines what can and cannot be claimed about nutritional supplements without prior Food and Drug Administration (FDA) review to prevent spreading misleading information.
Hospitals started recruiting dietitians and nutritionists in the late 19th century, after everyone started accepting the role of good nutrition in health.
Despite the great advances in this science, malnutrition due to deficiency or excess of nutrients is still present today. 👶
It shows how much health authorities worked in guaranteeing the adequate consumption and educating the use of food.
That is why the right nutrition knowledge is important for everyone.
Summary: We have been discussing nutrition and food for centuries. But modern nutritional science is surprisingly young. We have to find out a lot of information about nutrition to protect humanity.
Facts about Nutrition
Nutrition is the foundation for health and development. ⚕️
Better nutrition means a stronger immune system, fewer illnesses and better health for people of all ages.
After reading the following facts you will understand how important nutrition is. 🧐
- Roughly 2 billion people (about 30% of the world population) are affected by micronutrient deficiencies. 
- More than 1.9 billion adults (18 years or above) are overweight, of which more than 600 million are obese. 
- More than 38 million children (under five years old) are overweight. 
- More than 17 million people are dying every year from cardiovascular diseases. 
- Roughly 6.7 million people are dying every year, from insufficient fruit and vegetable consumption. 
Summary: Nutrition is a life process. Still in many countries lots of people suffer from malnutrition, either with poor or excess nutrition.
Now let me tell you the importance of nutrition in your daily life. 😋
Importance of Nutrition
According to Wikipedia, “Nutrition is the biochemical and physiological process by which an organism uses food to support its life.” 
But why do we need this “biochemical and physiological process” to survive? 🤔
For the following three reasons:
1. To Fulfil our Energy Needs
We need energy in the form of ATP to perform day-to-day activities like walking, reading or even sleeping.
If you think deeply, you can feel that while walking, our leg muscles work.
Our leg muscles are built with millions of cells.
Without energy, these cells can’t work, and ultimately you can’t walk.
I think you got my point.
So, the question is, from where does this energy come?
Yes, you guessed it right, from food. 🍲
But you may not know that we eat and use the food by a process called nutrition.
After eating, our digestive system breaks down the food and converts them into nutrients, which is a part of the nutrition process.
After that, nutrients like carbohydrates and fat are broken down further to produce energy in the form of ATP (Adenosine triphosphate).
Without nutrition, our body can’t produce ATP by using foods and our muscles or cells will not get energy to perform and we will die.
That’s why nutrition is important to live. 🙂
2. To Form and Maintain our Body Structure
The cell is the unit of life. 
Let me tell you an interesting fact. 🤩
When a group of cells perform a similar function, they form a tissue. When a group of tissues perform a similar function, they form an organ, like the stomach.
When a group of organs perform a similar function, they form an organ system, for example, the digestive system. The stomach is a part of our digestive system.
When multiple organ systems work harmoniously together, they form an independent organism like a human.
It’s like: Cells > Tissues > Organs > Organ System > Organism
So, you may think, how does the smallest unit, the cell, produce?
Our body produces cells with the help of food and nutrition.
Yes, by nutrition, our digestive system digests food and absorbs the nutrients and sends them to different parts of our body.
Our cells use these nutrients to grow, repair and produce new cells. 🦠
Not only cells, but our bones use nutrients to grow and repair. And here, too, the nutrition process comes into play.
3. To Prevent Diseases
Active lifestyle and proper nutrition can prevent many diseases like cold, stomach upset or allergy. 
But how? 🤔
An active lifestyle with proper nutrition strengthens our immune system. And a strong immune system protects us from diseases.
As I already discussed, when we eat food, our digestive system absorbs nutrients from the foods, by the process called nutrition.
Then our cells use those nutrients to perform their functions.
To boost our immune system, we need some nutrients in more amounts, like vitamin C, Vitamin E, Vitamin A and zinc.
What happens when we don’t eat enough food or the nutrition process doesn’t work properly?
We can’t get nutrients and become vulnerable to diseases. 🤧
Summary: Nutrition has three primary functions: fulfil our energy needs, form and maintain our body structure and prevent diseases.
Let me quickly tell you the functions and goals of nutrition.
Our body needs nutrition to carry out different functions like,
- Fulfill our energy needs
- Form and maintain our body structure
- Regulate different metabolic processes
- Prevent nutrition-related diseases.
Certain diets can often prevent many common diseases and their symptoms. 
For this reason, nutrition science tries to understand what are the specific dietary aspects that influence health.
The goal of nutrition is to ensure that our body has all the components, which come from food, necessary to keep our body in optimal health. 😮
Summary: Nutrition is the life process and ensures that our body has all the components to live.
Did you know different species follow different nutrition processes? Meaning they get their food by different mediums. 🤔
Let’s discuss the types of nutrition followed by different species.
Types of Nutrition
There are two types of nutrition among living organisms: autotrophic nutrition and heterotrophic nutrition. 
There is another type of nutrition, which is called mixotrophic nutrition. 
Let’s discuss one by one in detail. 👉
In this mode of nutrition, organisms can produce their own food. 
These organisms are called autotrophs or autotrophic organisms, or primary producers.
Autotrophs use carbon dioxide as the only carbon source and light or chemicals as an energy source.
There are two types of autotrophic nutrition: photosynthesis and chemosynthesis.
Organisms like plants, algae, and cyanobacteria use light as an energy source, are called phototrophs or photoautotrophs, or photolithoautotrophs.
They follow a procedure called photosynthesis. With this procedure, they absorb sunlight with their pigments for energy.
Even though phototrophs depend on light for their survival, some can grow under very low light conditions.
For example, organisms like certain bacteria use chemicals or inorganic compounds as an energy source. These organisms are called chemotrophs or chemoautotrophs, or chemolithoautotrophs.
They can’t use sunlight for energy because they live in deep water, and sunlight cannot reach there.
Bacteria follow a procedure called oxidation.
They oxidize or break down inorganic compounds like hydrogen sulfide, ammonia, sulfur dioxide, or ferrous ions to produce energy.
The procedure is called chemosynthesis.
In this mode of nutrition, organisms use already prepared substances, either by autotrophs or heterotrophs, called heterotrophic nutrition. 
These organisms are called heterotrophs or heterotrophic organisms.
Heterotrophs use organic compounds as a carbon source and produce inorganic compounds such as carbon dioxide as a waste product. Autotrophs use these inorganic waste products to produce their food. It creates a cycle called the nutrient cycle.
Heterotrophic organisms include animals, fungi, bacteria, and protozoa.
These organisms get their energy by breaking down the molecules of the autotrophic organisms that they have eaten.
Even carnivorous animals indirectly depend on autotrophs because the organisms they eat depend on autotrophs for living.
Different heterotrophic organisms get their nutrition in different modes. For example, parasitic, saprophytic and holozoic. 
Let’s discuss one by one. 🧐
In this mode, heterotrophic organisms live inside or outside of other organisms and obtain their food by ingestion or absorption.
These heterotrophs harm their host.
Those who live inside their host are called endoparasites.
And those who live outside or on the surface of their host are called ectoparasites.
In this mode, heterotrophic organisms live freely and get their nutrients from the environment.
They break those nutrients by enzymes to get the energy.
For example, fungi follow saprophytic nutrition. They are responsible for staling our bread.
In this mode, heterotrophic organisms ingest food and digest them to obtain nutrition.
For example, humans follow holozoic nutrition.
Now, holozoic nutrition can be classified further into three categories:
Herbivorous nutrition: Food source is vegetables
Carnivorous nutrition: Food source is meat
Omnivorous nutrition: Food source is both vegetables and meat.
In this mode, heterotrophic organisms share their food with hosts.
This mutual relationship may or may not be beneficial to both organisms.
For example, lichens establish symbiotic relationships with fungi and plants.
👉 According to the origin of energy, heterotrophic organisms can be divided into two categories:
In this mode, heterotrophic organisms use light as a source of energy.
For example, purple bacteria are heterotrophic and get carbon by absorbing organic matter and energy by absorbing sunlight.
In this mode, heterotrophic organisms use chemical compounds like carbohydrates, protein, and fat as energy sources.
For example, all the members of the animal kingdom and fungi, a large part of moneras and archaebacteria, use these chemical compounds for energy.
In this mode, heterotrophic organisms can get carbon from carbon gas as well as organic carbon.
In other words, they show both the characteristics of autotrophic nutrition and heterotrophic nutrition. 
These organisms can use light as an energy source or take it from organic or inorganic compounds.
For example, euglena has chloroplast for making their food by photosynthesis; however, they can also absorb nutrition from the environment. They usually live-in quiet ponds or puddles.
Summary: All living creatures need nourishment to survive. Different organisms get their nutrition in different ways. Some can produce their food on their own and some are dependent on someone. This created a nutrition cycle and it continues till the end of the earth.
Elements of Nutrition
Proper nutrition is complex. 🙂
It should be personalized and contain all the components or elements of nutrition.
There are 6 elements of nutrition for the human body.
Such as, carbohydrates, proteins, fats, vitamins, minerals, and water.
Let’s discuss one by one in detail. 🧐
This is a macronutrient made up of carbon, hydrogen and oxygen.
Carbohydrates / carbs / sugars / saccharides are the main energy source of our body.
The Dietary Guidelines for Americans recommend you should consume 45-65 percent of your total daily calories from carbohydrates. 
This is a macronutrient made up of carbon, hydrogen, oxygen, nitrogen, sulfur and phosphorus.
Protein molecules are often very large and can contain hundreds to thousands of amino acids.
According to the USDA’s Dietary Reference Intakes (DRI) an adult should consume 0.8 g of protein per kg of body weight. 
This is a macronutrient made up of carbon, hydrogen and oxygen.
Fat is the major storage form of energy in the body.
According to the USDA’s Dietary Reference Intakes (DRI) adults should consume 20-35% of their daily calories from fat. 
This is a micronutrient and organic compound.
The lack of vitamins can cause several disorders such as scurvy.
The Dietary Reference Intake (DRIs) of different vitamins are different. Check out the USDA’s official recommendations. 
This is a micronutrient and inorganic compound that represents 4 to 5 % of our body weight.
There are many minerals we need on a daily basis and the lack of it can cause several disorders like weak bones, fatigue or a poor immune system.
The Dietary Reference Intake (DRIs) of different minerals are different. Check out the USDA’s official recommendations. 
This is the main component of our body and represents two thirds of our body.
This simple, colorless, odorless and tasteless liquid is so important that without it we can’t survive.
According to USDA the recommended adequate intake (AI) value for total water for men aged 19+ is 3.7 liters each day and for women aged 19+ is 2.2 liters each day. 
Summary: We eat food and use it in the nutrition process. It ensures that our body has all the elements to live.
Did you know how food is used in our body? 🤔
Let’s discuss the different stages of human nutrition. 👉
Stages of Human Nutrition
As I already discussed, nutrition is a life process.
Nutrition involves 5 stages or steps: ingestion, digestion, absorption, assimilation and egestion.
Let’s discuss one by one. 👉
This is the first step of nutrition.
In this step, we take the food into our body through the mouth and break them by chewing with the help of teeth.
Also, saliva present in the mouth starts the initial digestion of the food.
This is the most important step of nutrition.
In this step, we broke down the foods further into absorbable form using different enzymes.
The digestion of different nutrients is different.
This is the second most important stage of nutrition.
In this step, we absorb digested foods or nutrients into the blood through the intestinal wall.
In this step our body cells take those absorbed nutrients from blood for energy, growth and repair.
This is the last step of nutrition.
In this step, we remove undigested foods and waste products from our body.
Summary: Nutrition is a life process, by which we get all the essential components to live. However, this process involves 5 stages or steps: ingestion, digestion, absorption, assimilation and egestion.
The Final Word
Nutrition is the foundation for health and development. ⚕️
Without the right nutrition, we can’t live a healthy life.
Despite the great advances in this science, malnutrition due to deficiency or excess of nutrients is still present today. 👶
That is why the right nutrition knowledge is important for everyone. 👍
FAQs about Nutrition
Finally, let me give you the answer to some common questions related to nutrition.
What is the basic definition of Nutrition?
Different organizations define nutrition in different ways, but the meanings are the same. However, the best nutrition definition according to NutritionCrown is, nutrition is a biological process of consuming foods to fulfill the dietary needs of our body.
Who discovered Nutrition?
Antoine Lavoisier, a prominent French chemist, discovered the concept of metabolism in 1770. He also showed that the oxidation of food is the source of body heat. That is why he is considered the father of nutrition.
Who is the Father of Nutrition in India?
Coluthur Gopalan (1918-2019), an Indian Nutritionist, is considered the father of nutrition research in India. He was responsible for different programs on anemia control, goiter prevention, Vitamin A supplementation, and the mid-day meal.
Who was the First Nutritionist?
Adelle Davis (1904-1974), an American nutritionist, is considered the first well-known nutritionist. She was an advocate for improved health through better nutrition. She is known for her famous quote on nutrition “Eat breakfast like a king, lunch like a prince, and dinner like a pauper.”
How many types of Nutrition are there?
There are two types of nutrition among living organisms: autotrophic nutrition and heterotrophic nutrition. There is another type of nutrition that exists, which is called mixotrophic nutrition.
How many types of Heterotrophic Nutrition are there?
There are four types of heterotrophic nutrition among living organisms: parasitic nutrition, saprophytic nutrition, holozoic nutrition, and symbiotic nutrition.
What are the different types of Autotrophic Nutrition?
There are two types of autotrophic nutrition among living organisms: chemosynthesis and photosynthesis.
What is the difference between Autotrophic and Heterotrophic Nutrition?
The main difference is, in autotrophic nutrition, organisms prepare their own food. But in heterotrophic nutrition, organisms do not prepare their own food. In the food chain, autotrophs are also called producers, and heterotrophs are called consumers.
Which organisms are both Autotrophs and Heterotrophs?
Some unicellular organisms carry both autotrophic and heterotrophic nutrition. For example, euglena has chloroplast for making their food by photosynthesis; however, they can also absorb nutrition from the environment.
What is another name for Heterotroph?
Another name of heterotroph is the ‘consumer’. Because they can’t produce food and depend on autotrophs or other heterotrophic organisms for food.
What is another name for Autotrophs?
Another name of autotroph is the producer because they produce their own food.
Are Human carnivores or herbivores?
Humans are omnivore animals but are more herbivores and less carnivores. Because most of our diet comes from plants and less from animals.
Can Humans be Autotrophs?
No. Humans can’t be autotrophs because humans can’t do photosynthesis. Also, our glucose demand is higher than what photosynthesis can accommodate.
What’s more important, taste or nutrition?
Nutrition is more important than taste. But without the taste you like, you can’t sustain your healthy eating. So, you need both. Eat tasty nutritious food, so your body and mind will be satisfied.
How to get nutrition when you can’t eat?
Try drinking warm fruits or vegetables juice after blending it with water and spices. You can also drink milk or use meal replacement supplements.
What is the difference between a nutritionist and dietician?
To be a dietician, you need a licence, while to be a nutritionist, you don’t need a proper licence. In many countries, a dietitian is protected by law, while a nutritionist is not.
What is the difference between nutrition and diet?
Diet refers to the food we eat to fulfil certain goals. Our habitual or religious eating is also known as diet. But nutrition is a biological process of consuming foods to fulfill the dietary needs of our body.
What is the difference between nutrition and exercise?
Nutrition provides energy for exercise. And regular exercise will help to fulfil the goal of nutrition.
This article is written by a certified nutritionist and verified by scientific evidence. ☑️
We rely on reputed and specialized media sites, academic research institutions, peer-reviewed studies, government agencies, and medical associations to source information. 📰
We avoid using tertiary references. Know more about how we ensure our content is accurate and current by reading our editorial policy. 🧐
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