Frequently Asked Questions [FAQs]

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Absorption process.

Absorption of the majority of nutrients takes place in the jejunum, with the following notable exceptions: Iron is absorbed in the duodenum. Vitamin B12 and bile salts are absorbed in the terminal ileum. Water and lipids are absorbed by passive diffusion throughout the small intestine.

Assimilation and Egestion process

Assimilation: is the process in which the absorbed food is taken in by the body cells and used for energy, growth, and repair. Blood carries the absorbed food to all the parts of the body.

Egestion: is the process in which the undigested food is removed from the body.



BMI stands for Body Mass Index
This is a numerical value of your weight in relation to your height. A BMI between 18.5 and 25 kg/m² indicates a normal weight. A BMI of less than 18.5 kg/m² is considered underweight. A BMI between 25 kg/m² and 29.9 kg/m² is considered overweight.



Carbohydrates, also known as saccharides or carbs, are sugars or starches. They are a major food source and a key form of energy for most organisms.

They consist of carbon, hydrogen, and oxygen atoms.

Two basic compounds make up carbohydrates:

Aldehydes: These are double-bonded carbon and oxygen atoms, plus a hydrogen atom.

Ketones: These are double-bonded carbon and oxygen atoms, plus two additional carbon atoms.

Carbs can combine to form polymers or chains.

These polymers can function as:

  • long-term food storage molecules
  • protective membranes for organisms and cells
  • the main structural support for plants

Most organic matter on earth is made up of carbohydrates. They are involved in many aspects of life.


There are various types of carbohydrates. They include monosaccharides, disaccharides, and polysaccharides.

Nutrition: Bread, pasta, beans, potatoes, bran, rice, and cereals are carbohydrate-rich foods. Most carbohydrate-rich foods have high starch content. Carbohydrates are the most common source of energy for most organisms, including humans.

We could get all our energy from fats and proteins if we had to. One gram of carbohydrate contains approximately 4 kilocalories (kcal), the same amount as protein. One gram of fat contains around 9 kcal.

However, carbohydrates have other important functions:

the brain needs carbohydrates, specifically glucose, because neurons cannot burn fat

dietary fiber is made of polysaccharides that our bodies do not digest

The United States (U.S.) Dietary Guidelines 2015-2020 recommend obtaining 45 to 65 percent of energy needs from carbohydrates, and a maximum of 10 percent should come from simple carbohydrates, in other words, glucose and simple sugars.

Carbohydrates Fast facts.

  • “Saccharide” is another word for “carbohydrate.”
  • Foods high in carbohydrates include bread, pasta, beans, potatoes, rice, and cereals.
  • One gram of carbohydrate contains approximately 4 kilocalories
  • High glycemic index (GI) carbohydrates quickly enter the bloodstream as glucose
  • Switching to a low-GI diet improves the chance of a healthy weight and lifestyle

Carbs and obesity

Some argue that the global rise in obesity is linked to a high intake of carbs. However, a number of factors contribute to this problem:

These include:

  • a reduction in physical activity
  • higher consumption of junk food
  • higher consumption of food additives, such as coloring, taste enhancers, and artificial emulsifiers
  • fewer hours of sleep each night
  • a rise in living standards

Stress may also be a factor. One study found that the molecule neuropeptide Y (NPY), which the body releases when stressed, can “unlock” Y2 receptors in the body’s fat cells, stimulating the cells to grow in size and number.

Rapidly developing countries, such as China, India, Brazil, and Mexico, are seeing a rise in obesity, as living standards and dietary habits change.

When these populations were leaner, their diets were more carb-heavy than they are now. They also consumed more natural produce and less junk food was more physically active and slept longer each night.


Cholesterol is a waxy, fat-like substance that occurs naturally in the body and is found in all cells. ... HDL ('good') cholesterol – HDL cholesterol carries cholesterol away from the arteries and back to the liver where it can be broken down.

Your body needs cholesterol to build healthy cells, but high levels of cholesterol can increase your risk of heart disease. With high cholesterol, you can develop fatty deposits in your blood vessels. ... Sometimes, those deposits can break suddenly and form a clot that causes a heart attack or stroke.


Digestion process.

Digestion is a process that breaks or dissembles the things that you eat into molecules small enough to be absorbed by cells that line the digestive tract. Ultimately these small molecules enter the cytoplasm of every cell in your body, where their nutritive value is utilized.


Disaccharides are two monosaccharide molecules bonded together, for example, lactose, maltose, and sucrose.

Bonding one glucose molecule with a galactose molecule produces lactose. Lactose is commonly found in milk.

Bonding one glucose molecule with a fructose molecule produces a sucrose molecule.

Sucrose is found in table sugar. It often results from photosynthesis, when sunlight absorbed by chlorophyll reacts with other compounds in plants.

Does your body need fat?

Fat is a type of nutrient, and just like protein and carbohydrates, your body needs some fat for energy, to absorb vitamins, and to protect your heart and brain health. For years we've been told that eating fat will add inches to your waistline, raise cholesterol, and cause a myriad of health problems.

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