Carbohydrates

Carbohydrates

• Carbohydrates make up the largest volume of our daily food.

• 60 % of our food should be from carbohydrates.

Carbohydrates are Macronutrients

• Macronutrients are nutrients that provide calories or energy. Nutrients are substances needed for growth, metabolism, and for other body functions. Since “macro” means large, macronutrients are nutrients needed in large amounts. There are three macronutrients: carbs, protein, and fat.

Simple vs. Complex Carbs

• Carbohydrates are classified as simple or complex. The classification depends on:

– the chemical structure of the food – how quickly the sugar is digested and

absorbed.

Simple vs. Complex Carbs

* Simple carbohydrates have one (single) or two (double) sugars.

* Complex carbohydrates have three or more sugars.

Glucose• Glucose is the major kind of simple sugar. It is

the basic source of energy for all living things.

• We are not able to make our own glucose, so we eat plants for their storage of glucose. We then burn glucose for energy.

• If you do not use the glucose, it gets turned into glycogen which is stored energy in the muscles and liver.

Single Sugar Carbs

• Examples of single sugars from foods include:

– Fructose (found in fruits)

–Galactose (found in milk products)

Fructose

• Fructose: known as fruit sugar. Most plants contain this sugar, especially fruits and saps.

• Fructose is a monosaccharide, a simple natural sweetener. It is the sweetest of the naturally occurring nutritive (caloric) sweeteners and has many unique functional and nutritional properties that make it a valuable food ingredient.

Fructose

• Fructose occurs naturally in fruits, vegetables and their juices, as well as honey. It gives these foods their sweet taste. Fructose in crystalline form has been widely used for the past 20 years as a nutritive sweetener in foods and beverages.

Galactose

• Galactose is in the same family as sucrose, fructose and lactose.

• Galactose is found in milk and whey, as well as the human body.

Double Sugar Carbs

• Double sugars include:

– Lactose (found in dairy)

–Maltose (found in certain vegetables and in beer)

– Sucrose (table sugar)

Lactose

• Carbohydrates come mainly from plant sources, although milk and milk products contain some carbohydrates in the form of lactose.

• Lactose: known as milk sugar, is found as the principal carbohydrate in milk.

Maltose

• Maltose: known as malt sugar, is found in grains.

Sucrose

• Sucrose: commonly known as table sugar, beet or cane.

• Sugar or more specifically sucrose is a carbohydrate that occurs naturally in every fruit and vegetable. It is the major product of photosynthesis, the process by which plants transform the sun's energy into food. Sugar occurs in greatest quantities in sugar cane and sugar beets from which it is separated for commercial use.

Simple Carbs

• Simple carbohydrates that contain vitamins and minerals occur naturally in:

– Fruits–Milk –milk products–Vegetables

Simple Carbs in refined foods

• Simple carbohydrates are also found in processed and refined sugars such as:–Candy–Regular (nondiet) carbonated beverages, such as soda– Syrups– Table sugar

Refined sugars explained• Refined sugars provide calories, but lack

vitamins, minerals, and fiber. Such simple sugars are often called "empty calories" and can lead to weight gain. Also, many refined foods, such as white flour, sugar, and white rice, lack B vitamins and other important nutrients unless they are marked "enriched." It is healthiest to get carbohydrates, vitamins, and other nutrients in as natural a form as possible -- for example, from fruit instead of table sugar.

Complex Carbs

• Complex carbohydrates:–Are often referred to as "starchy" foods

– include:• Legumes• Starchy vegetables•Whole-grain breads and cereals

Starch = Complex Carbs

• Starch in the body breaks down simple sugars. The body has to break down all sugar and starch into glucose to use it.

• All starchy foods are plant foods, seeds are the richest source; 70% of their weight is starch.

Fiber Dietary fiber, also known as roughage or bulk,

includes all parts of plant foods that your body can't digest or absorb. Unlike other food components such as fats, proteins or carbohydrates — which your body breaks down and absorbs — fiber isn't digested by your body. Therefore, it passes relatively intact through your stomach, small intestine, colon and out of your body. It might seem like fiber doesn't do much, but it has several important roles in maintaining health.

Fiber• Dietary fiber — found mainly in fruits,

vegetables, whole grains and legumes — is probably best known for its ability to prevent or relieve constipation. But fiber can provide other health benefits as well, such as lowering your risk of diabetes and heart disease.

• Fiber is commonly classified into two categories: those that don't dissolve in water (insoluble fiber) and those that do (soluble fiber).

Insoluble Fiber

• This type of fiber promotes the movement of material through your digestive system and increases stool bulk, so it can be of benefit to those who struggle with constipation or irregular stools. Whole-wheat flour, wheat bran, nuts and many vegetables are good sources of insoluble fiber.

Soluble Fiber

• This type of fiber dissolves in water to form a gel-like material. It can help lower blood cholesterol and glucose levels. Soluble fiber is found in oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium. (a type of plant- the seeds and husks are ground and used in foods)

Benefits of a high fiber diet

• Normalizes bowel movements.

• Helps maintain bowel integrity and health.

• Lowers blood cholesterol levels

• Helps control blood sugar levels.

• Aids in weight loss.

Sources of Fiber

Good choices include:

• Grains and whole-grain products• Fruits• Vegetables• Beans, peas and other legumes• Nuts and seeds

Poor Sources of Fiber

• Refined or processed foods — such as canned fruits and vegetables and pulp-free juice, white bread and pasta, and non-whole-grain cereals — are lower in fiber content. The grain-refining process removes the outer coat (bran) from the grain, which lowers its fiber content. Similarly, removing the skin from fruits and vegetables decreases their fiber content.

Why do we need carbs?

• Carbohydrates are the main source of fuel for the body.

• Carbohydrates are easily used for energy.

• Every tissue and cell in the body can use glucose for energy.

Why do we need carbs?

• Carbohydrates are the most efficient source of fuel for your muscles.

• An ample supply of carbohydrates is absolutely necessary to sustain a healthy existence and a must if your goal is to reduce your body fat and enhance your fitness level.

Why do we need carbs?

• Carbohydrates are the element of our food that supplies energy.

• Carbohydrates also play a vital part of the digestive process, and of the metabolism and oxidation of protein and fat.

What about low or no carb diets?

• These diets help you lose weight, BUT they are not healthy. The weight you lose will only be short term.

• Without carbohydrates, your body begins to burn glycogen reserves, so you lose that energy along with water weight.

• Glucose from carbohydrates provides energy for the nerve and brain cells. Don’t cut them out!

The Real Problem with Carbs• The issue with carbohydrates is that we eat too

many of the bad types of carbohydrates.

• Nearly two-thirds of our potatoes are processed into french fries and chips!

• Many of our juices have added sugar!

• Many people eat too many refined sugars such as candy and cakes.

Keeping carbs healthy

• To increase complex carbohydrates and healthy nutrients:– Eat more fruits and vegetables.

– Eat more whole-grain rice, breads, and cereals.

– Eat more legumes (beans, lentils, and dried peas).

**Read your food labels**

Recommended servings

• Here are recommended serving sizes for foods high in carbohydrates:

• Vegetables: 1 cup of raw vegetables, or 1/2 cup cooked vegetables, or 3/4 cup of vegetable juice

• Fruits: 1 medium-size fruit (such as 1 medium apple or 1 medium orange), 1/2 cup of a canned or chopped fruit, or 3/4 cup of fruit juice

Recommended servings

• Here are recommended serving sizes for foods high in carbohydrates:

• Breads and cereals: 1 slice of bread; 1 ounce or 2/3 cup of ready-to-eat cereal; 1/2 cup of cooked rice, pasta, or cereal

• 1/2 cup of cooked dry beans, lentils, or dried peas

• Dairy: 1 cup of skim or low-fat milk

Sources for this presentation

• http://www.mckinley.illinois.edu/handouts/macronutrients.htm

• http://www.nlm.nih.gov/medlineplus/ency/article/002469.htm

• http://www.fructose.org/facts.html

Sources for this presentation

• http://www.galactose.org

• http://www.elmhurst.edu/~chm/vchembook/546sucrose.html

• http://www.mayoclinic.com/health/fiber/NU00033