#HumanNutrition

#Biology

#DigestiveSystem

Introduction

• Human nutrition is the science that studies the nutrients in food and how the body uses them. It is crucial for maintaining health and preventing diseases.

• This means eating a wide variety of foods in the right proportions, and consuming the right amount of food and drink to achieve and maintain a healthy body weight.

• The necessary food groups are :

Carbohydrates

• Carbohydrates are essential nutrients that include sugars, starches, and fibers, serving as a major source of energy for the body.

• he Dietary Guidelines suggest that carbohydrates should constitute 45% to 65% of your total daily calorie intake. For a 2,000-calorie diet, this equates to approximately 225 to 325 grams of carbohydrates per day.

• Carbohydrates can be categorized into simple (monosaccharides and disaccharides) and complex carbohydrates (starches and fiber), affecting how quickly they provide energy.

Proteins

• Proteins are large biomolecules made up of one or more long chains of amino acids, essential for numerous functions in living organisms.

• There are 20 different amino acids that combine to form proteins in the human body.

• Out of these 20 amino acids, nine are classified as essential, meaning they cannot be synthesized by the body and must be obtained through diet.

• Aim for 20-25 grams of protein per meal to optimize muscle protein synthesis; more than that provides diminishing returns.

Lipids

• Lipids are a broad group of organic compounds including fats, oils, waxes, and certain vitamins that are primarily insoluble in water but soluble in organic solvents.

• Lipids help regulate hormones, transmit nerve impulses, cushion organs, and store energy in the form of body fat.

• Types of lipids include triglycerides, phospholipids, and steroids.

• Triglycerides are a type of fat, or lipid, that circulate in your blood and are the most common type of fat in your body.

• Phospholipids are a class of lipids that are a major component of cell membranes. They are made up of three main parts: Glycerol backbone, Phosphate group, and Two fatty acid chains.

• Steroids are strong medicines that help reduce inflammation and ease symptoms such as swelling, pain, and stiffness.

• For most people, neither a high- or low-fat diet is recommended for health. Getting 20–35% of your calories from fat—45–78 grams on a 2,000-calorie diet—is considered best for health. However, this amount may vary based on your health needs.

Vitamins

• Vitamins are organic molecules that are essential to an organism in small quantities for proper metabolic function.

• There are 13 essential vitamins, each serving unique roles in growth, development, and proper cellular function.

Minerals

• Minerals are those elements on the earth and in foods that our bodies need to develop and function normally.

• There are 21 Essential Minerals.

Water

• Water is a clear, nontoxic liquid that's essential for life and is made up of hydrogen and oxygen. It's the most common solvent and is the main component of the fluids in organisms.

• Regulates body temperature,

  Moistens tissues in the eyes, nose and mouth,

  Protects body organs and tissues,

  Carries nutrients and oxygen to cells,

  Lubricates joints,

  Lessens burden on the kidneys and liver by flushing out waste products, and

  Dissolves minerals and nutrients to make them accessible to your body.

• About 15.5 cups (3.7 liters) of fluids a day for men. About 11.5 cups (2.7 liters) of fluids a day for women.