Lipids
Key Definitions:
Lipids - the fat family including, triglycerides which are fats and oils.
Fats -lipids that are solid at room temperature vs. Oils -lipids that are liquid at room temperature.
Types of dietary fat (come as fats & oils):
· Saturated fats (bad) - animal meat fats, coconut oil, butter, lard, whole fat dairy products.
· Trans-fatty acids – a type of fat created when unsaturated oils are high pressure zapped & hardened. Found in commercially baked products and fast foods.
Saturated fats and trans fats are known as the “bad fats” because eating a diet high in in these can increase your risk of cardiovascular disease, certain types of cancer (colon & breast) and can lead to unhealthy weight gain.
· Monounsaturated fats (good) -olive, sesame & canola oils, avocado & nuts.
· Polyunsaturated fats (good) - sesame, pumpkin& sunflower seeds, fatty fish & tofu.
Monounsaturated fats and polyunsaturated fats are known as the “good fats” because they are good for your heart, reduce chances of heart disease & help lower your cholesterol.
Fat is an essential nutrient because it…
1. Provides backup energy - Although the main source of energy for our bodies is carbohydrates, fat is used as a source of backup energy in cases when carbohydrates are not available.
2. Absorb Vitamins - fat-soluble vitamins need fat in order to be absorbed and stored.
3. Maintains proper body temperature & protects your body – stored fat helps with thin layers of fat under the skin which keep us warm, and also layers of fat surrounding major organs (including the brain and heart), nerves, tissues and bones.
Fats are found in many foods and are a dense source of calories. In fact, fat has twice the number of calories as protein & carbohydrate.
· 1 gram of protein = 4 calories
· 1 gram of carbohydrate = 4 calories
· 1 gram of fat = 9 calories 4.
Myth: Fat-free means healthy!
Fact: A “fat-free” label doesn’t mean you can eat all you want without consequences to your waistline. Many fat-free foods are high in sugar, refined carbohydrates, and calories.
CARBOHYDRATES
What are carbohydrates?
Carbohydrates (or carbs) include are sugars and starches which provide an important source of energy in our diets.
Most food items we consume contain carbohydrates. All fruit and vegetables, all breads, grains and cereal products are carbohydrates as well as sugars and sugary foods.
Some foods have more carbohydrates in them than others, pasta, bread, rice, kumura, baked goods, fruits, vegetables and cereals.
Two Types of Carbohydrates
There are two major types of carbohydrates (or carbs) in foods: simple and complex
· Simple carbohydrates are broken down quickly by the body to be used as energy. Simple carbohydrates are found naturally in foods such as fruits, milk, and milk products. They are also found in processed and refined sugars such as candy, table sugar, syrups, and soft drinks.
· Complex carbohydrates are broken down more slowly in the body as they are often rich in FIBRE, thus satisfying hunger for longer and promoting healthier eating habits. Complex carbohydrates are commonly found in whole plant foods.
The majority of carbohydrate intake should come from complex carbohydrates (starches) and naturally occurring sugars rather than processed or refined sugars.
Why do we need Carbohydrates??
· Carbohydrates are the body's main source of energy (calories) and are a key fuel source for daily movement, thinking (carbs are the only fuel source for the rain) and exercise and sport.
What does the Glycaemic Index of carbohydrates mean?
Different carbohydrate-containing foods are digested and absorbed at different rates. Like Simple vs. Complex carbohydrates, the Glycaemic Index (GI) is the classification used to identify which carbohydrates are quickly broken down to glucose (high GI) and which are slowly broken down (low GI).
Examples of medium and low GI carbohydrate foods include: Wholegrain and seeded breads and pasta, brown and basmati rice, oats and muesli, beans, most fruit and vegetables.
Low GI = you feel fuller for longer
DIETRY FIBRE! Its 1 of the 7 essential nutrients
is found in edible plant foods such as cereals, fruits, vegetables, dried peas, nuts, lentils and grains. Fibre consumption has been found to reduce appetite as it slows food absorption and makes you feel fuller for longer, which prevents overeating leading to obesity. Fibre is also aids in digestion by absorbing water to soften faeces for normal bowel motions.
VITAMINS & MINERALS
What Are Vitamins and Minerals?
Vitamins and minerals are essential nutrients because they perform hundreds of roles in the body. They boost the immune system, support normal growth and development, and help cells and organs do their jobs. They also convert food into energy for movement, and repair cellular damage (heal wounds and illness).
For example vitamin K, helps blood to clot (so cuts and scrapes stop bleeding quickly). You'll find vitamin K in green leafy vegetables, broccoli, and soybeans.
And to have strong bones, you need to eat foods such as milk, yogurt, and green leafy vegetables, which are rich in the mineral calcium.
Micronutrients with a big role in the body
Vitamins and minerals are often called micronutrients because your body needs only tiny amounts of them. Yet failing to get even those small quantities virtually guarantees disease. Examples:
· Scurvy. Old-time sailors learned that living for months without fresh fruits or vegetables—the main sources of vitamin C—causes the bleeding gums and listlessness of scurvy.
· Blindness. In some developing countries, people still become blind from vitamin A deficiency.
Vitamins fall into two categories: fat soluble and water soluble.
The fat-soluble vitamins — A, D, E, and K — dissolve in fat and can be stored in your body. They:
· Build bones. Bone formation would be impossible without vitamins A, D, and K.
· Protect vision. Vitamin A also helps keep cells healthy and protects your vision.
· Interact favourably. Without vitamin E, your body would have difficulty absorbing and storing vitamin A.
The water-soluble vitamins — C and the B-complex vitamins (such as vitamins B6, B12, niacin, riboflavin, and folate) — need to dissolve in water before your body can absorb them. Because of this, your body can't store these vitamins. Any vitamin C or B that your body doesn't use as it passes through your system is lost (mostly when you pee). So you need a fresh supply of these vitamins every day. These vitamins:
· Release energy. Several B vitamins help release energy from food.
· Build proteins and cells.
Whereas vitamins are organic substances (made by plants or animals), MINERALS are inorganic elements that come from the soil and water and are absorbed by plants or eaten by animals. Your body needs larger amounts of some minerals, such as calcium, to grow and stay healthy. Other minerals like chromium, copper, iodine, iron, selenium, and zinc are called trace minerals because you only need very small amounts of them each day.
Although you get vitamins and minerals from the foods you eat every day, some foods have more vitamins and minerals than others
PROTEIN
What happens to proteins in the body?
Approximately one-fifth of our body weight is protein. Proteins are part of the structure of every cell and body tissue including hair, nails, blood, skin and bones. All proteins are made up of smaller units or building blocks called amino acids. When we eat protein in foods it is broken down by our digestive system into amino acids. The amino acids are then put back together inside our body cells in many different combinations to make new proteins like the ones already in our bodies. In order for the body to grow or repair itself, all amino acids must be available to the body at the same time and in the right proportions.
Your body uses protein to build and repair tissues. You also use protein to make enzymes, hormones, and other body chemicals. Protein is an important building block of bones, muscles, cartilage, skin, and blood. Along with fat and carbohydrates, protein is a “macronutrient,” meaning that the body needs relatively large amounts of it. But unlike fat and carbohydrates, the body does not store protein, and therefore has no reservoir to draw on when it needs a new supply.
Overall the body uses protein to:
*renew and/or repair cells and body tissues
*grow (to make new cells and tissues)
*make body proteins such as enzymes, some hormones and antibodies to fight infection
*supply energy (after carbohydrates)
List of High-Protein Foods
Meat (Beef, Fish, Chicken, Pork), Dairy (eggs, milk), Vegetables (peas, lentils, beans), some nuts like peanuts.
Recommended Daly Protein Intake
• The average adult needs 0.8 grams per kilogram (2.2lbs) of body weight per day.
• Strength training athletes need about 1.4 to 1.8 grams per kilogram (2.2lbs) of body weight per day
• Endurance athletes need about 1.2 to 1.4 grams per kilogram (2.2lbs) of body weight per day