Source: BMI Chart; Public Domain http://en.wikipedia.org/wiki/File:*********************.svg
Welcome to this lesson today on nutrition and health. Today we are going to be taking a look at the role nutrition and health play on your body. So we're going to start by identifying parts of your diet that can play a role in your body. And important parts of your diet include vitamins, minerals, and nutrients. So let's identify what the difference is between these and examples of each.
So vitamins are organic substances that you take in as you eat food. So some common examples of vitamins you might be familiar with are vitamin C, vitamin D, Vitamin K, Vitamin E. These are all examples of vitamins that you've probably heard of before and that are important parts of your diet, among many other different types of vitamins.
But let's just discuss two of these today. Vitamin D, for example, is a vitamin that can actually be made in the skin, but also can be obtained through diet by eating things like fish, egg yolks, milk, et cetera. So the importance of vitamin D is in bone growth, calcium absorption, and immunity.
So it plays a role in making sure that bones grow and develop. It also helps calcium to be absorbed more easily by your body. And it plays a role in your immune system, in enhancing the immune system.
Vitamin C is a vitamin that is obtained through fruits, especially citrus fruits or berries. Vitamin C is often associated with like orange juice or oranges. So it's high in citrus fruits, but also can be found in veggies, especially green veggies like broccoli, for example.
Minerals, on the other hand, are inorganic substances. So examples of minerals would be like calcium, iron, magnesium, et cetera. So there are also tons of different types of minerals that you get from the foods you eat.
So let's just take a look at calcium as one example. So calcium is most often associated with dairy foods, such as milk, cheeses, ice cream, things of that nature, things that are dairy foods. It can also be found though in green veggies and a few other foods as well. So it's important for bone formation, blood clotting, and for the functioning of the nervous system and muscles.
And the nutrients are things like carbohydrates, lipids, and proteins. So carbohydrates are necessary in your diet because they are broken down into glucose and then used by your body as an energy source. So complex carbs are the most healthy type of carbohydrate, versus simple carbohydrates.
Lipids are also known as fats. And they're needed for cell membranes, for energy, and for cushioning of your organs. So some fats are healthier than others, so it's best to avoid the unhealthy fats and stick towards more the healthier fats. So for example, olive oil is an example of a healthy fat, whereas like french fries would be an example of an unhealthy fat.
And proteins are nutrients that are needed for protein synthesis in our body. And they also help with muscle building.
So essential fatty acids and essential amino acids have to be obtained by our diet. So they can't be made by our bodies, but instead they have to be obtained by our diet. So some types of fatty acids and some types of amino acids our body can make on its own. But others need to be obtained through diet.
So for example, cholesterol is a type of fatty acid that our body makes on its own. Other fatty acids that our body needs are called essential fatty acids. And those are taken in by our diet, through things like vegetable oils, for example.
Essential amino acids are amino acids that our body cannot produce on its own. So there are actually 20 amino acids. Eight of them are essential. So eight of those 20 cannot be made by the body itself, so we get those through our diet.
And then the last thing I want to mention here about diet is that fiber is important to have in our diet, even if it doesn't provide a lot of nutritional value. But the importance of fiber basically is to add bulk to help push food through our digestive system. So diverticulosis and hemorrhoids are examples of possible outcomes if our diet is lacking in fiber. So there's various different types of foods that have fiber in them. Fruits and foods that have a lot of wheat or things like that, for example, in them help provide fiber to add bulk to push food through our digestive system.
In this part of the lesson here we're going to take some time to talk a little bit about BMI, body fat, and healthy weight loss. So we're going to start by discussing BMI. And this is a term that you've probably heard before. And what this stands for is Body Mass Index.
So a BMI is a measurement of a person's height relative to their weight. So it uses a person's height and weight to measure the amount or the percentage of body fat that they have. And there's actually an equation that goes along with it, which is weight times 703 divided by height squared. So you can use that in order to find your BMI.
But an easier way generally is just to use a BMI table, like the one that you can see here. So I'm going to zoom in so we can take a look at this table a little bit more closely. So as you can see on this table, and as I mentioned, BMI uses height and weight to measure a person's body fat. So we have height and weight on our table here.
So depending on if you prefer to measure in meters and kilograms or feet and inches and pounds is up to you. You'll get the same results. I'm going to go ahead and use the feet and inches and pounds, because that's what I'm familiar with.
So basically how you use this table is you look up your height and your weight. And it'll tell you what category you're in based on those numbers, whether you're underweight, in a normal range, overweight, or obese. So my height, I'm about 5'8", which falls right around here in this range. And I weigh 135 pounds. So if we scroll over here, you would find that my BMI falls in this range right here. So I would be in the normal range for my weight relative to my height.
So you'll notice here that a person who is obese has a BMI of over 30. So we characterize obese as being a BMI of over 30. So I'm going to zoom out again so we can see the whole page here. OK.
So a BMR stands for Basal Metabolic Rate. And basically BMR is the amount of energy needed to sustain body functions. So it tells you how many calories do you need to sustain your body functions. And this BMR is going to vary from person to person, depending on the person's size, their age, their activity level, et cetera. So it's telling you how many calories you need intake per day to sustain your body functions and to maintain your body weight.
If a person wanted to lose weight, they would then find their BMR, or how many calories are needed to sustain the body functions, and then they would eat less calories than that in order to lose weight. So losing one pound of fat is equal to about expanding 3,500 calories. So having some fat in the body is important. It helps to cushion organs. It helps to provide energy. But having too much fat in the body can be detrimental to health.
So again, obesity is a BMI of over 30. So basically this table is letting you know the healthy range of height versus weight. And you want to be somewhere in the normal category. So in order to be in that normal category, in order to have a healthy amount of body fat, exercise and nutrition are both important in that. So exercising to help maintain that normal amount of body fat, but also eating the right foods and eating healthy, a combination of those is a good way in order to maintain a healthy body weight.
So this lesson has been an overview on nutrition and health.
A measurement ratio of your height and weight to assess a person’s body composition that is often used as a health and disease indicator.
A class of organic compounds that are the body’s main source of energy; carbohydrates are sugars that can be found as monosaccharides (glucose), disaccharides (fructose), and polysaccharides (starch).
Amino acids we cannot naturally synthesize are called essential amino acids; since we cannot synthesize them we must consume them in our diet.
Fatty acids we cannot naturally synthesize are called essential fatty acids; since we cannot synthesize them we must consume them in our diet.
Long hydrophobic hydrocarbon chains that act as the body’s main source of stored energy along with other secondary functions.
Inorganic elements found in soil that are involved in almost every metabolic process of the human body.
Having too much body fat, not to be confused with being overweight, this means weighing too much. Obesity is a risk factor for many chronic diseases such as hypertension, type II diabetes, cardiovascular disease etc.
Large, complex polymers of amino acids that have diverse functions (structure, communication, identity, immunity, carriers, etc.)
A diverse class of organic compounds that are involved in almost every metabolic process in the human body.