The Basics of Nutrition

Though there are many diets that promote going to certain extremes or unusual practices to achieve change in your body, the truth is there are a few fundamental concepts that will decide how effective any diet will be.

To understand how effective any diet will be, you just need to understand two concepts: energy balance, and macronutrients.

Every diet you’ve ever heard of relies on those two ideas, and governs how effective that diet will be in transforming your body.

We’ll be breaking down these concepts in this article, and give you the basic knowledge you’ll need to then design your own diet for muscle growth or fat loss!

Energy Balance

The most important part of any nutritional plan is understanding energy balance. 

Whether a diet is keto, paleo, low-fat, or gluten-free, how a diet affects your weight just comes down to how it affects your energy balance.

Energy Balance refers to the relationship between the energy you burn and the calories you take in each day.

What this means is if you consistently take in more calories than you burn, you will be in a positive energy balance and will gain weight. On the other hand, if you consistently burn more calories than you take in, you will be in a negative energy balance and will lose weight.

If you understand that concept, you may be wondering how to figure out how many calories you burn every day? Fortunately, there is a way to figure this number out. It’s called your Total Daily Energy Expenditure, or TDEE.

Total Daily Energy Expenditure (TDEE)

Your Total Daily Energy Expenditure (TDEE) is how much energy you expend every day measured in calories. TDEE serves as your baseline when measuring how to eat in order to gain or lose weight.

Your TDEE is made up of 3 components:

1. Your base metabolic rate (BMR)
2. Daily physical activity
3. Thermogenesis

We’ll explain each of these components here!

Base Metabolic Rate

In layman’s terms, your Base Metabolic Rate (BMR) is the amount of energy your body uses so that you can be alive each day. That means that BMR is the energy it takes for you to breathe, or the energy it takes to keep blood circulating in your body. It is essentially the amount of energy you need to keep your body functioning. Your BMR accounts for 60-75% of your TDEE.

The amount of energy your body takes to function is something that is personal to you. While your BMR is partially determined by genetics, studies show that increasing the amount of lean muscle in your body can increase your BMR because your body uses extra energy to maintain muscle mass on a daily basis.

Studies show that working out can also temporarily boost your BMR for a short period of time. This means with daily exercise, you can not only burn extra calories through exercising, but also through boosting your BMR.

Daily Physical Activity

The next piece of your TDEE is Daily Physical Activity. In simple terms, Daily Physical Activity is the energy you use to move around every day. This includes daily movement like from climbing the stairs at work to running or lifting weights at the gym.  

Daily Physical Activity accounts for 15-30% of your TDEE.

Anything involving general movement contributes to the Daily Physical Activity portion of your TDEE. Your Daily Physical Activity includes physical movement such as walking around, and of course the energy you expend while training or exercising.

If you want to increase the number of Daily Physical Activity calories you burn, you can take some simple steps such as taking the stairs instead of the elevator, going on a walk, or exercising more.

Thermogenesis

Thermogenesis is the energy your body uses in order to digest the food that you eat. 

Thermogenesis makes up the last 10% of your TDEE.

Some types of foods take more energy than others to digest. For example, protein from something like chicken takes more energy to break down than sugars from a chocolate bar.

Eating foods that are harder to break down technically will increase the calories you burn through thermogenesis, but not to the degree that will make a large difference in your overall TDEE. If your aim is to burn more calories, you’re better off exercising instead of aiming for thermogenesis-enhancing foods!

How to Calculate Your TDEE

With this basic understanding of the components of your TDEE, the next step is figuring out what your own TDEE is. 

To start, you’ll need to estimate your TDEE using an online calculator.

Once you have an estimate of your TDEE, you will have to track your daily caloric intake as well as your weight to figure out if the estimate is accurate. For every pound you gain per week, you are taking in roughly 500 calories above your TDEE per day (and vice versa for every pound lost). 

So if the calculator estimated your TDEE to be 2000 calories, and after a week of eating 2000 calories a day you gain 1 lb, then your TDEE is actually 1500 calories (500 less than the estimate). If you lost a pound that week, then your TDEE is actually 2500 calories (500 more than that estimate). If your weight stayed the same, then the estimate is correct and your TDEE is 2000 calories!

Macronutrients

So far, we’ve covered how eating above or below your TDEE can help you gain or lose weight. Studies have shown that  you could literally eat a diet of Twinkies and still manage to lose weight if you make sure you are eating fewer calories than you are burning.

If you want to adjust your diet to control what kind of weight you are gaining or losing, though, you have to consider your macronutrient intake.

There are three primary macronutrients in any diet:

1. Protein
2. Fats
3. Carbohydrates

Here is what you should know about each macronutrient as it concerns your diet!

Protein

Proteins are the building blocks responsible for the growth and maintenance of your eyes, skin, hair, nails, organs, and of course, muscle tissue. You get protein from a variety of sources including both animals and plants.  

There are many sources of protein, but some of the most common sources are:

1. Meats like chicken or beef
2. Dairy products like yogurt or cheese
3. Fish like salmon or tuna
4. Eggs
5. Grains like bread or pasta
6. Nuts like almonds or walnuts
7. Legumes like green peas or black beans

There are 4 calories per gram of protein in food; that is to say for every 1 gram of protein you consume translates to 4 calories of energy intake. 

Fat

Fats are another type of macronutrient in the everyday diet.

Many articles and videos about how fats are bad for you, but this is actually incorrect! Your body needs to have some fat in order to function.

Fat is essential to your body’s cells and genetic makeup. Fats make up cell membranes, cholesterol, and 60% of your brain. They play an important role in maintaining hormonal balance in your body, and absorbing vitamins and nutrients, and maintaining cell health. 

There are 9 calories per gram of fat in food which makes fat the most calorically dense macronutrient.

This means that fats not only serve as a critical source of energy for your body, but they also should be consumed in moderation. Greasy snacks and even nuts have a high fat content, which means a potentially unexpected number of calories. 

Regardless of what diet you follow, research suggests you consume 15-25% of your calories in fats. This figure will remain constant regardless of whether you are trying to gain muscle or lose fat, and is critical to maintain a healthy body.

Carbohydrates

Carbohydrates (commonly referred to as carbs) are the main source of energy for you during everyday life and exercise.

There are 4 calories per gram of carbohydrate you consume, just like in protein. There are many sources of carbohydrates, but in a typical diet they come from sugars, starches, and fibers found in fruits, grains, vegetables, and milk products.

So What’s Next? 

Now that you understand the concepts of energy balance and the utility of each macronutrient, you have the information you need to build a diet for either muscle growth or fat loss. 

Check out our Fat Loss Nutrition and Muscle Growth Nutrition articles, if you’re interested in applying these foundational concepts to crafting your own diet for fat loss or muscle growth.

Conclusion

This wraps the basics of nutrition! In this article, we covered:

• If you consistently take in more energy than you burn, you will be in a positive energy balance and will gain weight. 
• Likewise, if you consistently take in less energy than you burn, you will be in a negative energy balance and will lose weight.
• Your TDEE will tell you how much energy you burn each day, and it is composed of your base metabolic rate (BMR), daily physical activity, and thermogenesis.
• Your macronutrient balance will determine what kind of weight you gain or lose.
  • Protein will help you retain or gain muscle. Consume between 0.8g to 1.2g of protein per pound of bodyweight. 
  • Fats maintain an optimal hormonal balance and provide a secondary source of energy. Make sure to have at least 15% of your total caloric intake from fat to maintain hormonal health.
  • Carbohydrates are your main source of energy. Eating between 2.7 and 4.5g of carbs for each pound you weigh is ideal for athletic performance, but going below that amount is common in order to make room for protein and fat in calorically strict diets.

The exact numbers of calories and macronutrients you should aim to take in will depend on whether you want to build muscle or gain fat, and you can read more about that in our Fat Loss Nutrition and Muscle Growth Nutrition articles.

References and Useful Research

1. Hall KD, Heymsfield SB, Kemnitz JW, Klein S, Schoeller DA, Speakman JR. Energy balance and its components: implications for body weight regulation. Am J Clin Nutr. 2012;95(4):989-94. Link
2. Poehlman ET. A review: exercise and its influence on resting energy metabolism in man. Med Sci Sports Exerc. 1989;21(5):515-25. Link
3. Zurlo F, Larson K, Bogardus C, Ravussin E. Skeletal muscle metabolism is a major determinant of resting energy expenditure. J Clin Invest. 1990;86(5):1423-7. Link
4. Knab AM, Shanely RA, Corbin KD, Jin F, Sha W, Nieman DC. A 45-minute vigorous exercise bout increases metabolic rate for 14 hours. Med Sci Sports Exerc. 2011;43(9):1643-8. Link
5. Sutton EF, Bray GA, Burton JH, Smith SR, Redman LM. No evidence for metabolic adaptation in thermic effect of food by dietary protein. Obesity (Silver Spring). 2016;24(8):1639-42. Link
6. Medline Plus. Protein in diet: MedlinePlus Medical Encyclopedia. https://medlineplus.gov/ency/article/002467.htm. Published 2019. Accessed January 30, 2019. Link
7. Helms ER, Zinn C, Rowlands DS, Brown SR. A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes. Int J Sport Nutr Exerc Metab. 2014;24(2):127-38. Link
8. Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr. 2014;11:20. Link
9. Kim JE, O'connor LE, Sands LP, Slebodnik MB, Campbell WW. Effects of dietary protein intake on body composition changes after weight loss in older adults: a systematic review and meta-analysis. Nutr Rev. 2016;74(3):210-24. Link
10. Murphy CH, Hector AJ, Phillips SM. Considerations for protein intake in managing weight loss in athletes. Eur J Sport Sci. 2015;15(1):21-8. Link
11. Pasiakos SM, Cao JJ, Margolis LM, et al. Effects of high-protein diets on fat-free mass and muscle protein synthesis following weight loss: a randomized controlled trial. FASEB J. 2013;27(9):3837-47. Link
12. Phillips SM, Van loon LJ. Dietary protein for athletes: from requirements to optimum adaptation. J Sports Sci. 2011;29 Suppl 1:S29-38. Link
13. Phillips SM. A brief review of higher dietary protein diets in weight loss: a focus on athletes. Sports Med. 2014;44 Suppl 2:S149-53. Link
14. Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance. Med Sci Sports Exerc. 2016;48(3):543-68.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4960974/ Link
15. Jéquier E. Carbohydrates as a source of energy. Am J Clin Nutr. 1994;59(3 Suppl):682S-685S. Link
16. Achten J, Halson SL, Moseley L, Rayson MP, Casey A, Jeukendrup AE. Higher dietary carbohydrate content during intensified running training results in better maintenance of performance and mood state. J Appl Physiol. 2004;96:1331–40. Link
17. Casey A, Short AH, Curtis S, Greenhaff PL. The effect of glycogen availability on power output and the metabolic response to repeated bouts of maximal, isokinetic exercise in man. Eur J Appl Physiol Occup Physiol. 1996;72:249–55. Link
18. Garthe I, Raastad T, Refsnes PE, Koivisto A, Sundgot-borgen J. Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab. 2011;21(2):97-104. Link
19. Erlenbusch M, Haub M, Munoz K, MacConnie S, Stillwell B. Effect of high-fat or high-carbohydrate diets on endurance exercise: a metaanalysis. Int J Sport Nutr Exerc Metab. 2005;15:1–14. Link
20. Fleming J, Sharman MJ, Avery NG, et al. Endurance capacity and high-intensity exercise performance responses to a high fat diet. Int J Sport Nutr Exerc Metab. 2003;13:466–78. Link
21. Pizza FX, Flynn MG, Duscha BD, Holden J, Kubitz ER. A carbohydrate loading regimen improves high intensity, short duration exercise performance. Int J Sport Nutr. 1995;5:110–6. Link
22. Lambert CP, Frank LL, Evans WJ. Macronutrient considerations for the sport of bodybuilding. Sports Med. 2004;34(5):317-27. Link
23. Bird SP. Strength nutrition: maximizing your anabolic potential. Strength Cond J. 2010;32:80–86. doi: 10.1519/SSC.0b013e3181d5284e. Link
24. https://www.ncbi.nlm.nih.gov/pubmed/21558571