In the further text, we will answer the question “What are proteins?”, and talk about the significance of different types of proteins for our body. After that, you will be able to give a few examples of proteins and maybe even tell your friends what is the function of proteins present in our blood. You will also learn the recommended daily protein intake according to DRI nutrition guidelines (dietary reference index). We won't leave you with just the theory, though. A list of foods high in protein and a recipe for a banana protein shake already await you! Finally, we will cover the topic of children from developing countries suffering from chronic protein deficiency.
Naturally, you cannot maintain healthy eating habits on protein alone. Head straight to our macronutrients calculator for a comprehensive overview of an ideal diet.
What are proteins? – protein definition
Proteins, just like carbohydrates and fats, are macronutrients - substances used by organisms to produce energy and sustain basic bodily functions. Being organisms, proteins are essential to our existence; Different types of proteins not only build our muscles, but also regulate our hormones and metabolism. Some of them are antibodies - without proteins, our immune system wouldn't work at all.
There is also another group of proteins, albumins. These globular proteins are found in our blood, and travel through the blood vessels of our body. Albumins serve many roles. They transport various substances that need to get to every part of our body: cations (Na⁺, K⁺, Ca²⁺, Mg²⁺), fatty acids, bilirubin, hormones (including thyroxine) and some pharmaceuticals (if administered). It has some serious clinical implications. Clinicians should remember that the serum calcium and magnesium levels can be altered due to hypoalbuminemia – a state of low albumin level in blood serum. Acquired Ca²⁺ and Mg²⁺ levels have to be corrected using special equations. Our corrected calcium calculator and corrected magnesium calculator use them and perform calculations for doctors!
Albumins are also responsible for keeping an adequate oncotic blood pressure. It is the force that keeps the blood inside the arteries and veins. When there is a low serum albumin level, the patient may suffer from edemas, where fluids escape the bloodstream, enter the tissues, and stay there. Clinicians use this knowledge to determine the source of ascites (an excess of fluid inside the peritoneal cavity). Visit our serum-ascites albumin gradient calculator to learn more on this topic.
If proteins are so important, where can you find them? Well, there are many different sources of protein. The most popular ones are animal foods, such as meat, fish, and dairy products. However, it is also possible to plan a vegetarian or even a vegan diet with a sufficient amount of protein. Beans and nuts are some examples of non-animal sources. We will give you a list of foods high in protein in further paragraphs.
When on a vegan or vegetarian diet, it's best to consult a professional dietitian to make sure that you are consuming sufficient amounts of various macronutrients, including protein.
Now, if your friends ask you: "what is the function of proteins?", you can already elaborate on many topics considering proper functioning of our body and mention a few examples of proteins. It is time to answer the question: "How much protein do I need?".
How much protein do I need? - recommended protein intake
While many bodybuilders follow the "the more, the merrier" rule when planning their protein intake, the truth is that our bodies are not able to utilize a lot of protein at once. If you eat an enormous steak, only a fraction of it will be used by our cells. The rest will be converted into carbohydrates for energy. Now, how much protein per day should you eat?
There are many different approaches to estimating how much protein per day should be supplied to our bodies. Typically, we should keep the percentage of proteins in the total calorie intake at 10-15%. Our protein calculator uses exactly these values.
Other recommendations, such as the one issued by the Food and Nutrition Council of the National Research Council, gives the maximum allowed amount of proteins in grams per kilogram of body mass. An adult should consume about 0.8 g protein per kilogram of body weight per day. This value can be higher for infants, pregnant women, or athletes. The National Institutes of Health guidelines provide, in turn, a fixed amount of recommended daily protein supply depending on a person's sex and age. We will talk more about this in the DRI – nutrition guidelines paragraph.
If you want to recalculate calories of protein into grams, you should use the following equation:
4 kcal = 1 g
This protein intake calculator uses this formula to estimate your recommended daily protein. Please note that the 10-15% requirement is valid for people without special diets (e.g., diabetic diet) - if you need a personalized eating plan, consult a dietitian.
DRI – nutrition guidelines
If you would like to deepen your knowledge on which nutrients you should eat and in what quantity, we encourage you to visit the webpage of the National Institutes of Health. You will find there DRI – nutrition guidelines. The DRI comes from dietary reference index. These indexes consist of many different tables presenting data on the recommended supply of any particular nutrient for each sex and age group. We have used them to prepare this table of recommended protein intake:
|Life Stage Group||Protein (g/d)|
|> 18 y||56|
|> 13 y||46|
|Pregnancy and lactation||71|
How to use our daily protein calculator?
This is an instruction on how to use our daily protein calculator:
- Select your sex - choose between male and female.
- Type in your height. Please note that you can choose from a variety of units of length, just click on the default -
- Measure and type in your weight – here, you can also choose the unit of weight.
- Type in your age.
- Select your activity level throughout a week.
- That’s it! Your suggested daily protein intake should appear in the
Caloriesfield. You didn't have to perform complex calculations or look through large nutritional tables. Our daily protein calculator did it all for you!
Foods high in protein
You already know how much protein per day you should eat to preserve your well-being, but do you know what you can eat to supply proteins effectively? Do you know any foods high in protein? Don't worry. We have prepared a list of foods high in protein especially for you:
- Meat: beef, pork, lamb, turkey and chicken breasts;
- Fish: tuna, halibut, and salmon;
- Dairy products: milk, cottage cheese, yogurt;
- Nuts and seeds: hemp seeds, almonds, pumpkin seeds, pistachios, chia seeds, and nut butter;
- Plants and corns: black beans, lima beans, yellow corn, potatoes, broccoli, cauliflower, cabbage, oats, legumes, sun-dried tomatoes, guava, artichokes, peas, chickpeas, quinoa, lentils, avocado, and asparagus;
- Spirulina – biomass produced by cyanobacteria – blue-green algae;
- Whey protein powder – used as a supplement by heavy lifters and athletes wanting to build up muscle mass. In the next paragraph, we will give you a recipe for a banana protein shake!
Have you ever wondered how many calories you should eat with every particular meal throughout a day? Now you can calculate it by yourself with our meal calorie calculator!
Banana protein shake
Many athletes and bodybuilders help themselves gain muscle weight by supplementing their diet with whey protein powder. However, not so many of them like the taste of protein powder simply dissolved in water or milk. If it also applies to you, don't worry! We have prepared a recipe for a delicious banana protein shake! The bananas and peanut butter included in the recipe will alter the taste of protein shake, thus making it easier to consume. And even if you like whey protein powder by itself, it is nice to have a little change once in a while, isn't it?
Banana protein shake recipe:
- 1 cup of milk – low-fat, almond or any other – it's your call!
- 1 banana, cut into small pieces;
- 3 tablespoons peanut butter;
- 1/3 teaspoon of vanilla extract;
- 1 scoop of whey protein powder – preferably vanilla flavor;
- Some ice cubes if you like it frozen.
- Add all ingredients to the blender or your hand blender bowl.
- Blend until it's smooth – you can check it by tasting with a teaspoon.
- It's ready. Bon appetite! Hope you like it!
Proteins and weight loss
If you're trying to lose weight, it is essential that you keep your protein intake at a level recommended by this protein calculator. A decrease in protein consumption can have a detrimental effect on your health.
The reason behind it is quite simple. When we reach a calorie deficit, our bodies don't automatically start burning the accumulated fat (even though we would wish for it). First, they use the available carbohydrates and proteins. Only then they turn to fat storage for energy.
Accessing the fat storage is not easy, though - it requires some energy, which is usually obtained from breaking down carbohydrates. If these are not available, your organism will break down lean body tissues (yes, your muscles) for proteins that can be converted into carbs.
What does it mean? It means that if you try a starvation diet, instead of losing fat, you will lose muscle mass. That's why it is recommended to eat small portions of protein a few times throughout the day - so that your cells will not have to turn to its own tissues as an energy source.
If you want to stay fit and in shape, we invite you to visit our calories burned calculator. It is a fantastic tool for losing additional pounds that will keep you motivated throughout your training. How much fat is there to lose? Check it with our lean body mass calculator that will tell you your body weight without fat tissues.
Protein deficiency – when the hunger kills
We would like to end this text by addressing a grave tragedy affecting an unbelievable amount of people around the world – the protein-energy malnutrition. It is caused by chronic hunger or disease reducing the ability of intestines to absorb food. As you may suspect, it concerns mainly developing countries. However, children and the elderly of America experience the malnutrition and protein deficiency too. This illness manifests in two disorders: marasmus, a state of inadequate supply of both proteins as well as calories, and kwashiorkor in which enough calories are consumed but with a protein deficiency. Emaciation is the most characteristic feature of marasmus, while edemas are typical for kwashiorkor (go back to the "What are proteins? – protein definition" paragraph to learn why).
Both malnutrition and protein deficiency cause changes in practically every part of the human body (as it affects various types of proteins in different organs):
- Loss of muscle and fat mass;
- Dry, thin, atrophic skin with pigmentation alterations;
- Depigmentation and loss of hair;
- Fatty and enlarged liver (hepatomegaly) with reduced protein production;
- Protuberant abdomen;
- Problems with digestion;
- Bradycardia (slow heartbeat) and decreased stroke volume;
- A decrease of vital capacity, tidal volume, and minute ventilation of lungs;
- Malfunction of kidneys: decreased glomerular filtration rate (click here for pediatric GFR calculator), ability to excrete acid and sodium;
- Anemia, leukopenia, and lymphocytopenia (a decrease in the amount of red, white cells and lymphocytes);
- Weak immune system;
- Hormone disturbances;
- Death - around 5 000 000 deaths of young children in developing countries occur each year because of malnutrition.
We, the people of the 21th century, hear about discoveries or inventions on a daily basis. We are proud of our technological advancement, open-mindedness, and humane way of thinking. However, we still let such tragedies happen in front of our eyes. Perhaps society should be judged on how it is treats its weakest members? What do you think about it?