What Are Macronutrients? Our Needs and Top Sources - Dr. Axe

Fact Checked

This Dr. Axe content is medically reviewed or fact checked to ensure factually accurate information.

With strict editorial sourcing guidelines, we only link to academic research institutions, reputable media sites and, when research is available, medically peer-reviewed studies. Note that the numbers in parentheses (1, 2, etc.) are clickable links to these studies.

The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.

This article is based on scientific evidence, written by experts and fact checked by our trained editorial staff. Note that the numbers in parentheses (1, 2, etc.) are clickable links to medically peer-reviewed studies.

Our team includes licensed nutritionists and dietitians, certified health education specialists, as well as certified strength and conditioning specialists, personal trainers and corrective exercise specialists. Our team aims to be not only thorough with its research, but also objective and unbiased.

The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.

3 Macronutrients You Need and Top Food Sources


Macronutrients - Dr. Axe

Each and every food that we eat, whether it’s a cheeseburger or green smoothie, contains a proportion of different macronutrients. It’s common for the highest percentage of macronutrients found in the food to actually be how we classify or refer to the food — for example, calling grains and potatoes “carbs” and meat or fish “proteins.”

Given all of the attention they get in the dieting and bodybuilding scenes, you might be wondering what are macronutrients exactly (commonly called”macros” for short)? What are some of the reasons why people might decide to start tracking or counting macros in their diets?

As you’ll learn more about below, keeping track of the macro ratios in your diet might be able to help you achieve some positive changes in terms of your athletic performance and body composition, just as knowing the micronutrients you’re getting can help fight aging and disease. While it’s not totally necessary to track every detail of your macro intake, it helps to have a good understanding of what macros are, the benefits each one has and proportions that might be best for you to aim for depending on your goals.

What Are Macronutrients?

By definition, macronutrients are “energy providing chemicals” or “substances required in relatively large amounts by living organisms.” The calories we consume from the foods in our our diets are categorized into different macronutrients depending on how they’re metabolized and the purposes they serve once digested.

In the human diet there are three primary macronutrients that are founds in all types of foods: fats, proteins and carbohydrates. We cannot live without all three of these macronutrients even for a short period of time, as they’re needed for everything from growth and development to sustaining circulation and providing the brain with enough energy for cognitive functioning.


Most diets emphasize all three macronutrients, such as the macrobiotic diet.

Macronutrients vs. Micronutrients

We use measurements of macronutrients in different foods to describe how many calories they provide (think “big” when you hear macro), while we use measurements of micronutrients to describe levels of vitamins, minerals, enzymes, etc., found in a given food. (Think small, since these are found in trace amounts compared to overall calories.)

  • We need both macros and micronutrients to keep our bodies running, since together they supply us with energy, help with production of hormones, nourish our tissues and organs, help produce enzymes, and carry out processes responsible for repair, growth and development.
  • Micronutrient is the common term for vitamins and minerals that the body requires in trace amounts. Examples of micronutrients you’re likely familiar with include vitamins A, C, E and D; all B vitamins; zinc; selenium; iron; magnesium; and calcium.
  • There are dozens of micronutrients present inside in the body, each one with different roles and uses. For example, vitamins that are often called “antioxidants” (like vitamin C, A and E) help control inflammation, keep us protected from bacteria and viruses, and help with repairing tissue injuries. Selenium is another mineral important for metabolism since it’s involved in the production of the enzyme glutathione peroxidase, known as a “master antioxidant.” B vitamins help transport electrons and supply us with energy. Electrolytes like calcium, potassium and magnesium are needed to balance fluid levels, control muscular movements, maintain bone strength, help with digestion by preventing acid buildup, regulate high blood pressure and much more.
  • No single type of food contains all of the many micronutrients we need, which is why variety in your diet is key. Eating different food groups (vegetables, fruit, starchy plants, legumes or sprouted grains, meat, and dairy, for example) helps provide us with enough of all three macronutrients, in addition to enough micronutrients.

Related: 11 Foods That Make You Taller (and Why They Do)

Why We Need Macronutrients

Each of the three major macronutrients — proteins, fats and carbs — has important and distinct roles in the body when it comes to weight management, hormonal balance, immunity, development and so on. Here are some of the most important reasons why we need each macronutrient:

1. Proteins

  • Proteins provide four calories per gram, the same amount as carbohydrates but less than fats. Protein foods are made of amino acids, commonly called “the building blocks of the body.”
  • There are nine amino acids that are considered “essential” for health, which we must obtain from our diets since our bodies cannot make them on their own.
  • Some of the roles that amino acids/proteins have include helping form and maintain muscle mass, providing energy for our cells and brain, helping store away energy for later use in fat stores, making your heart beat, helping build the foundation of vital organs — including your heart, lungs and even your DNA — and supporting growth/development.
  • Because of its ties to lean muscle mass and satiety in terms of controlling your appetite, protein is especially important as you age. Protein deficiency can contribute to weakness, mood changes and more. A lack of protein in your diet can cause side effects/symptoms, including muscle weakness or muscle wasting, loss of concentration, weight gain or weight loss (depending on if body fat is increased), anxiety, joint discomfort, and trouble sleeping.
  • During our growth and development stages when we are younger, we require the most protein in proportion to body weight. Young children need about 1–1.5 grams of protein per kilogram of body weight, while older children and adults need around 0.8–0.95 grams of protein per kilogram of body weight. The need for protein also goes up during pregnancy in order to help grow the developing fetus, up to about 1.1–1.3 grams of protein per kilogram of pre-pregnancy weight.
  • Protein is constantly broken down and used for energy, so you need to replenish your body’s supply on a daily basis by consuming foods that supply protein. (Both plant and meat sources can do this.) Sources include eggs, yogurt, meat, beans and fish (more on this below).

2. Carbohydrates

  • Carbohydrates, like protein, provide four calories per gram. The body breaks down various carbohydrate foods (whether simple or complex) into glucose, which is used easily for energy or saved away in muscles and fat stores for later use.
  • Carbs are the body’s preferred, No. 1 energy source. However, they aren’t the only macronutrient that supplies energy to cells. This is why it’s possible to follow a low-carb diet and still have enough energy, endurance and muscular strength.
  • Carbohydrate foods are digested at different speeds depending on how much fiber, protein and fat they have. Refined and processed carbs release glucose (sugar) into the bloodstream more quickly, leading to symptoms like low energy levels, cravings, overeating, weight gain and brain fog. Eating lots of processed/fast carbs can also increase risk for insulin resistance and diabetes.
  • Slow carbs” like veggies, whole pieces of fruit, ancient grains and legumes, provide a slower release of glucose and better supply of energy for our cells that lasts for longer.

3. Fats

  • Fats provide nine calories per gram, making them the most energy-dense macronutrient. However, fats don’t make you fat — they’re actually another source of energy for the body and important for controlling your appetite. In fact, fats are a totally essential part of the diet and also capable of helping with weight management and disease prevention.
  • Healthy fats in your diet have the roles of protecting your vital organs, regulating hormone production (including of reproductive hormones like estrogen and testosterone), helping regulate your body temperature, allowing for proper absorption of fat-soluble vitamins, providing your brain with fuel, protecting you from depression and anxiety, and many more.
  • It’s best to get a variety of fats in your diet, including those that provide monounsaturated fats (like olive oil or avocados), polyunsaturated fats (like omega-3s from fish, nuts and seeds) and, yes, saturated fats too (like grass-fed beef, coconut oil, or milk and raw dairy). Eating different types of fats won’t increase your risk your heart disease. In fact, it can help raise levels of “good” cholesterol (HDL) while lowering the “bad” (LDL) kind.

Note: In addition to these three macronutrients, alcohol can be another source of calories (energy) in our diets.

Alcohol has seven calories per gram, putting it between carbs/protein and fats. Ethyl alcohol (ethanol) is the type used in beverages we consume, which are usually produced by the fermentation of grains and fruits, resulting in anywhere from 2 percent to 20 percent alcohol by volume. (Beer has the least calories and alcohol based on volume, while hard liquor has the most.)

Top macronutrient food sources - Dr. Axe

Related: The Best Postnatal Vitamins for Mom and Baby

Is There One Macronutrient We Need Most?

To reiterate, all three macronutrients are important for survival, not to mention for optimal health, longevity, happiness and feeling your best. Here are several things to keep in mind regarding your intake of the three macronutrients:

  • While every person needs all three macronutrients to survive, the amount of each (protein, fat or carbs) in someone’s diet varies widely from person to person. Some people choose to focus on increasing or decreasing one specific macronutrient, such as fat or carbs, in order to achieve weight loss, muscle gain or other benefits.
  • Even if you’re increasing carbs and protein (for example, you’re an endurance athlete or trying to build muscle/lose weight), note that your fat intake should never go below 15 percent of your total calories, as this can cause unwanted side effects.
  • If on the other hand you’re looking to lose weight and therefore are cutting carbs, keep in mind this doesn’t mean you should aim to eat no carbs. You need at least some carbs in your diet for energy, endurance and hormone balance, especially if you’re a woman, you’re already on the thinner side, or you’re active or an athlete.

While every macronutrient diet plan is different, here are some common macronutrient ratios depending on your fitness/body weight goals:

  • For help with weight loss and burning more fat: Lower the amount of carbs in your diet, especially from processed grains and added sugar. A standard macro ratio for losing weight might be about 10 percent to 30 percent of your calories coming from carbs (note: this is considered very low carb, or the ketogenic diet), 40 percent to 50 percent from protein, and 30 percent to 40 percent (or more) from fat.
  • If you want to build muscle: Building muscle requires eating enough calories and generally supplying muscles with carbs and protein, so aim for a ratio of about 40 percent to 60 percent calories from carbs, 25 percent to 35 from protein and 15 percent to 25 percent from fat.
  • If you’re very active or an endurance athlete: Aim for about the same ratio as building muscle, possibly with even a bit more carbs (up to 70 percent or so).
  • If you simply want to maintain: Opinions differ here, but most authorities recommend getting about 30 percent to 50 percent of calories from carbs, 20 percent to 30 percent from protein and 25 percent to 35 percent from fat.
  • If you’re looking to gain weight because you’re underweight: Increase your intake of carbs and fats, which can boost your overall calorie intake and allow you to eat enough. You might aim for about 50 percent to 70 percent carbs, 15 percent to 20 percent protein and the remainder from fats.

Should You Count Macronutrients?

IIFYM,” which stands for “If It Fits Your Macros,” is a type of dietary plan that works by counting macros and usually calories too.

Those following an IIFYM diet plan typically calculate how many grams of each macronutrient they need each day depending on their goals (i.e., weight loss, building muscle, etc.). IIFYM followers then either plan meals carefully to provide the right amount of each macronutrient or eat basically whatever they’d like as long as they stay within the limits for these goals (in other words, “as long as they fit their macros”).

Is IIFYM a good idea? IIFYM might help you reach your fitness or weight-related goals in the short term — plus it might teach you a few things in the process, such as which foods are very high in empty calories or which help you feel most satisfied/fullest for longest.

However, I recommend thinking about what’s even of higher importance: the need to cut out lots of processed, empty calories from your diet, learning moderation and focusing on eating wholesome foods the majority of the time.

Related: What Is the Zone Diet? Meal Plans, Benefits, Risks & Reviews

Top Food Sources

Best Sources of Healthy Protein:

  • Bone broth or protein powder made from bone broth — 1 serving: 20 grams
  • High-quality whey protein powder  — 1 serving: ~20 grams
  • Grass-fed beef  — 3 ounces: 19 grams
  • Organic lentils  — 1 cup: 18 grams
  • Wild-caught fish (like wild Alaskan salmon, mackerel, tuna, etc.) — 3 ounces salmon: around 17 grams
  • Organic chicken — 1 chicken breast: 16 grams
  • Raw milk — 1 cup: 8 grams
  • Free-range eggs — 1 large egg: 7 grams

How many grams of protein per day do you need? For the average person, I recommend getting enough protein in your diet by consuming at least half your body weight in protein every day in grams. So, for instance, if you weigh 150 pounds, you should consume at least 75 grams of protein.


For athletes or anyone trying to build lean muscle (including while also burning fat and reducing cravings), you likely need even more.

In addition to providing protein, each type of animal protein offers other benefits too, so vary the types you have. For example, chicken or beef liver is packed with B vitamins, iron and vitamin A. Cage-free eggs offer multiple nutrients, including choline, vitamin A and vitamin E.

Focus on buying grass-fed, pasture-raised, wild or cage-free animal proteins. When applicable or available, choose “USDA Organic” or “Certified Organic” protein foods that are free of synthetic additives like growth hormones, pesticides, GMOs, chemical fertilizers, etc. Look for those raised humanely and without antibiotics.

Best Sources of Healthy, Unprocessed Carbohydrates:

  • All types of vegetablesLeafy greens (like kale, collard greens, spinach, bok choy, cabbage and romaine lettuce) are still low in carbs and very low in calories. They’re excellent sources of vitamin C, vitamin A, vitamin K, folate and magnesium. Considering how low in calories many veggies are, feel free to load up with every meal if you’d like. Other good choices include peppers, broccoli, squash, cauliflower, green peppers, artichokes, carrots, asparagus, tomatoes and mushrooms. Try filling half your plate with a mix of veggies as often as you can.
  • Starchy root veggies — These include potatoes, sweet potatoes, winter squash, cassava and other tubers, which contain many micronutrients and fiber in addition to carbs from starch.
  • Fruits (especially berries) — Strawberries, blueberries, raspberries, melon, pineapple, apples, pears and kiwis are high in antioxidants like flavanoids, vitamin A and C, fiber, and potassium. Berries, in particular, are associated with brain health and cancer prevention, which is why they have high ORAC values (oxygen radical absorption capacity), meaning they help fight free radicals.
  • Beans/legumes — Some of the best sources of fiber, beans are great for digestion and controlling cholesterol. They’re also a good plant-based source of protein and high in calcium, manganese, folate, phosphorus and iron.
  • Sprouted ancient/whole grains — Ancient sprouted grains like quinoa, rice, amaranth, gluten-free oats and buckwheat provide carbs mostly but also some protein too. They’re also good sources of nutrients like fiber, B vitamins, manganese, iron and phosphorus. I recommend eating modest amounts, about one serving per day (if you can tolerate them).

Best Sources of Healthy Fats:

  • Coconut oil, milk and flakes — Coconuts are rich in medium-chain fatty acids, which are easy for your body to digest, used to help provide the body with energy, and capable of improving brain and memory function. High amounts of natural saturated fats in coconut oil mean that it increases good cholesterol and promotes heart health, in addition to boosting digestive and hormonal health.
  • Extra virgin olive oil (EVOO) — EVOO is great for heart health, provides lots of monounsaturated fats and is even a source of certain antioxidants. Studies suggest olive oil can help protect memory and cognitive function in the elderly, works as an anti-inflammatory, and is linked with better emotional/mental health. Avocados also offer monounsaturated fats and make another great choice.
  • Butter and ghee — These are other good sources of saturated fats that can help control your appetite, add flavor to foods and help with hormone production.
  • Nuts/seeds — These provide omega-3 fatty acids and high levels of fiber, plus some protein, too. Try to include seeds like chia, flax and hemp as well as nuts like almonds and walnuts.
  • Wild-caught fish — Fish like salmon, mackerel, halibut, tuna and anchovies are great sources of anti-inflammatory omega-3 fatty acids, as are walnuts and flaxseeds.
  • Grass-fed/pasture-raised/wild animal products — Although they’re thought of as protein sources more so than fat sources, many animal products also provide some fat, including conjugated linoleic acid and omega-3s. Liver, wild seafood, cage-free eggs, grass-fed beef and pasture-raised poultry (dark meat) are sources of fatty acids and many micronutrients too (like iron, B vitamins, vitamin A and zinc).


Most experts feel that counting macros (or calories) is not really necessary long term if you take each meal one by one, focusing on eating unprocessed foods first and foremost, and planning meals and snacks in a balanced way. This approach doesn’t require strict tracking, counting or obsessing, so it provides more flexibility and might be easier to sustain for more than a short time period.

Balanced meals throughout the day — meaning the kinds that include different whole food groups, colors, variety, etc. — also provide at least some of all three major macronutrients you need. If you vary the types of you foods you eat, for example including different types of proteins in your meals (plants vs. animal sources) and different veggies, then you should get adequate micronutrients too.

Final Thoughts

  • Macronutrients are compounds found in all foods that humans consume in the largest quantities, providing the bulk of our calories (energy) from our diets.
  • The three main categories of macronutrients are carbohydrates, fat and protein. We need all three to stay healthy, but amounts in each person’s diet can differ a lot depending on weight, genetics, level of activity, goals, etc.
  • Macronutrients are sometimes referred to as “macros.” Some people choose to count and track their macro intake (a plan called IIFYM) in order to boost weight loss, build muscle, increase exercise performance, etc., though it’s not always necessary, particularly if you take each meal one by one, focusing on eating unprocessed foods first and foremost, and planning meals and snacks in a balanced way.

More Nutrition