Sunday, November 30, 2008

Recommended Caloric Intake

Most people have heard of a Calorie. Some people know that it's for energy, but exactly how much energy does it produce? One Calorie is able to raise the temperature of 1 gram of water up to 1 °C. One pound of body fat is equivalent to 3500 calories. Let's say part of the schedule of a busy teenager includes running three miles every day. Since one mile burns about 100 calories, that teenager would burn up to 300 calories in one run. To make up for this calorie loss, a busy teenager would probably need to eat a snack or larger lunch, compared to a normal teenager. Most teenagers go to a regular school where they learn, take tests, socialize, and eat. If we generalized a busy teenager then, he/she would burn extra calories doing sports and playing an instrument. The estimated "extra" calories being burned would be approximated from anywhere ranging from 300-1,000 calories a day.
These calories are of course "extra" because it doesn't include a teen's basal metabolic rate. A basal metabolic rate is the number of calories burned if someone didn't do anything all day. If they stayed in bed all day and didn't move, this would be the number of calories they burn. As you get older, your basal metabolic rate decreases. This is why it is important to do sports. Sports increase your cardiovascular fitness and help build muscles. Someone who is fit and has muscles will burn more calories than someone who has a body composition of mostly fat.

This is the recommended intake of carbohydrates, protein, and fat for a regular teenager: 45-60% of carbs for total caloric intake, 15% of protein for total caloric intake, and 30% of fat for total caloric intake. The recommended intake of a busy teenager would have a higher percentage of carbohydrates (around the higher end-- 60%), and if they do sports, around 20% of protein to build muscle. Also, there should be no higher than 10% of saturated fat in the overall diet.
There are three general types of fat: saturated, unsaturated, and trans fat. Out of these three, two of them are unhealthy. Each category has the same about of calories (9 calories per gram). A saturated fat is one that clogs arteries and raises LDL cholesterol levels. These are mainly dairy products, so beef, bacon, cheese, butter, biscuits and crisps are examples of some. Though most of them are meat & dairy products, some can be found in plants or vegetable oils. An unsaturated fat is one that comes from vegetables/plants. There are two types of them: monounsaturated and polyunsaturated. Monounsaturated fats are found in olives, nuts, peanut oil and canola oils. Some of these fats can have the opposite effect of saturated fat. They can lower LDL cholesterol. The other type of unsaturated fat is polyunsaturated fat. Corn and sesame are examples of this fat. Overall, unsaturated fat includes sunflower oil, olive oil, rice oil, nuts, rapeseed oil, and oily fish (such as sardines). Fats are the secondary source of energy after carbohydrates.

Protein is important for growth and the repairing of muscle/body tissue. The extra protein in ones body is converted into fat. Since busy teenagers are active, they need protein to have strong muscles. If they are injured, protein and vitamins are also vital for healing. Proteins are large compounds made up on amino acids. Amino acids are simple organic compounds, and the essential amino acids cannot be synthesized. To learn more about the chemical makeup of and essential amino acid, go here: http://hyperphysics.phy-astr.gsu.edu/hbase/organic/essam.html
Examples of common proteins are meat, poultry, fish, nuts, soybeans, eggs, milk, legumes, soymilk, cheese, yogurt, and tofu. Complete proteins include foods such as milk, fish, and meat. They are animal proteins and contain ample amounts of essential amino acids. Incomplete proteins are vegetable proteins. They include grains, nuts, and seeds. Complete proteins are important because incomplete proteins are missing essential amino acids.

45-60% of a teenager's total caloric intake should be devoted to carbohydrates. Carbs are the primary energy source for a person because it contains sugars. The sugars are quickly converted into glucose, so the energy can be ready to use by the body. There are many types of carbs: simple sugars, glucose, fructose, and galactose. Examples of carbohydrates are cereal, bread, rice, pasta, fruit, grains, crackers, pancakes, vegetables, and sweets. Simple and complex carbs are different because simple carbs are the refined sugars. They also include fruits and milk. The complex carbs are starches. Starches are grain products. Some are healthier than others, but unrefined grains are good fiber sources. Brown rice vs. white rice is a great example of an unrefined grain vs. a refined grain. Since the brown rice still contains its nutrients, it is healthier than the white rice. Corn, oats, potatoes, yams, and whole grained cereals/breads are examples of a complex carb. Since refined sugars aren't as healthy, they should only make up 11% of your caloric intake. This means 34-49% (the rest of the carbohydrates) should be complex starches.

Here is a short video explaining one of the specific dietary needs of a busy teenager:


There are also two important minerals that should be included in everyone's diet-- teenagers especially. They are iron and calcium. As the lady in the above video mentioned, kids ages 9-18 should get 1300 mg of calcium a day. However, if you don't get this much calcium a day, don't sweat it. At the very minimum, guys should get 1000 mg a day and girls should get 800 mg. Calcium is so important because it prevents osteoporosis as you age. It especially prevents hip and wrist fractures from happening too often. Calcium builds strong bones, and a person's teenage years are when the most calcium is absorbed into the bones. Take advantage of this!
Teenagers should also eat lean beef because it contains iron, but not as much fat as regular beef. So many kids in America suffer from iron deficiency, so make sure to get the recommended iron intake. Teenage boys ages 14-18 need 11 mg of iron a day, while teenage girls (also ages 14-18) need 15 mg a day.

2 comments:

Jenna said...

Awesome movie! So cool! Gives lots of good information.

Morgan said...

I like how you incorporated a video into this area. It adds a little more interest for the viewer/reader.