Carbohydrate benefits

The right kind of carbohydrates can be incredibly good for you. Not only are they necessary for your health, but they carry a variety of added benefits.

Mental health

Carbohydrates may be important to mental health. A study published in 2009 in the journal JAMA Internal Medicine found that people on a high-fat, low- carbohydrates diet for a year had more anxiety, depression and anger than people on a low-fat, high- carbohydrates diet. Scientists suspect that carbohydrates help with the production of serotonin in the brain.

Carbohydrates may help memory, too. A 2008 study at Tufts University had overweight women cut carbohydrates entirely from their diets for one week. Then, they tested the women's cognitive skills, visual attention and spatial memory. The women on no- carbohydrates diets did worse than overweight women on low-calorie diets that contained a healthy amount of carbohydrates.

Weight loss

Though carbohydrates are often blamed for weight gain, the right kind of carbohydrates can actually help you lose and maintain a healthy weight. This happens because many good carbohydrates, especially whole grains and vegetables with skin, contain fiber. It is difficult to get sufficient fiber on a low- carbohydrates diet. Dietary fiber helps you to feel full, and generally comes in relatively low-calorie foods.

A study published in the Journal of Nutrition in 2009 followed middle-age women for 20 months and found that participants who ate more fiber lost weight, while those who decreased their fiber intake gained weight. Another recent study linked fat loss with low-fat diets, not low- carbohydrates ones.

Good source of nutrients

Whole, unprocessed fruits and vegetables are well known for their nutrient content. Some are even considered superfoods because of it — and all of these leafy greens, bright sweet potatoes, juicy berries, tangycitruses and crunchy apples contain carbohydrates.

One important, plentiful source of carbohydrates is whole grains. A large study published in 2010 in the Journal of the American Dietetic Association found that those eating the most whole grains had significantly higher amounts of fiber, energy and polyunsaturated fats, as well as all micronutrients (except vitamin B12 and sodium). An additional study, published in 2014 in the journal Critical Reviews in Food Science and Nutrition, found that whole grains contain antioxidants, which were previously thought to exist almost exclusively in fruits and vegetables.

Revision exercises

Ex.1. Answer the following questions:

1. What are carbohydrates? 2. What functions do carbohydrates perform? 3. What are structural isomers? 4. What is the difference between aldoses and ketoses? 5. What do the properties of a polysaccharide molecule depend on? 6. What are the carbohydrate benefits for mental health? 7. What did a large study published in 2010 in the Journal of the American Dietetic Association find? 8. What did an additional study, published in 2014 in the journal Critical Reviews in Food Science and Nutrition discover?

Ex.2. Match the words with their definitions:

1. sugar	a. the process of breathing;
2.Benedict's reagent	b. a substance that carries genetic information in the cells of the body;
3. fuel	c. to divide into parts or categories or to separate (as a chemical compound) into simpler substances;
4. respiration.	d. a sweet white or brown substance that is obtained from plants and used to make food and drinks sweet;
5. RNA	e. to be the cause of (a situation, action, or state of mind);
6. DNA	f. is a polymeric molecule implicated in various biological roles in coding, decoding, regulation, and expression of genes;
7. break down	g. a chemical commonly used to detect presence of reducing sugars, however other reducing substances also give a positive reaction;
8. result in	h. a substance such as coal, gas, or oil that can be burned to produce heat or energy.

Ex.3. Say whether the following statements are true or false:

1. Monosaccharides and disaccharides are often called sugars. 2. Monosaccharides have the general molecular formula (CH2O)n, where n can be 2, 4 or 8. 3. Monosaccharides containing the aldehyde group are classified as ketoses. 4. The most important carbohydrate fuel in human cells releases energy when the molecules are metabolized. 5. Fructose reacts with glucose to make the dissacharide lactose.6. Most sugars found in nature are monosaccharides. 7. The women's cognitive skills, visual attention and spatial memory are better if they consume a healthy amount of carbohydrates every day.

Ex.4. Insert the necessary word:

1. Starch is manufactured in the green leaves of plants from excess glucose produced during … . 2. It serves the plant as … . 3. Starch is stored in chloroplasts in the form of granules and in such organs as … of the tapioca plant; … of the potato; … pith of sago; and … of corn, wheat, and rice. 4. When required, starch is broken down, in the presence of certain … and water, into its constituent monomer glucose units, which diffuse from the cell … the plant tissues. 5. In humans and other animals, starch is broken down into its … sugar molecules, which then supply energy to the …. (the roots, tissues, photosynthesis, the tuber, constituent, to nourish, a reserve food supply, the seeds, enzymes)