Essential Knowledge for Healthy Eating

Starting to eat healthily takes willpower—but figuring out what actually works for our bodies can feel overwhelming with so much conflicting advice. A solid understanding of nutrition is the key to breaking this cycle.

When we know what we’re eating and why, we can make confident choices, address cravings, and build lasting habits. This blog simplifies the basics of nutrition, cutting through the noise to help you take the first step toward better health.

Nutrients

Nutrients are essential substances that our body needs to function properly and that we can’t produce ourselves; we need to obtain them from our diet. There are three main types of nutrients: macronutrients, micronutrients, and water. Alcohol also exists in our diet, but since it has no nutritional value, we won’t include it as a nutrient. Macronutrients include proteins, carbohydrates, and fats, while micronutrients include vitamins and minerals. (reference)

Macronutrients vs. Micronutrients

1. Water

The most crucial nutrient is water. We often overlook water as a nutrient and instead look for supplements or doctors for solutions, when sometimes the answer is simple: drink a glass of water. Water makes up about 60% of our bodies and is essential because all biochemical processes in our body take place in water. Interestingly, when we’re not in the habit of drinking enough water, we don’t feel thirst as intensely as we would if we drank water regularly. The general recommendation is that women drink 9 cups, and men 13 cups of water daily—though, of course, this varies, as each body is different. (reference; reference)

Before diving into micro- and macronutrients, let’s get familiar with the measurement unit kcal, which is used for macronutrients (as micronutrients and water don’t contain calories). We see calories everywhere and may even count them ourselves (average daily intake: 2,500 kcal for men and 2,000 kcal for women), but what are calories, really?

DID YOU KNOW?

Calories are units of measurement for the maximum amount of energy we can obtain from specific foods. However, we typically don’t get the full amount due to digestion and the loss to microorganisms in our stomach; we absorb a reasonable portion, usually around 100%. A kcal is measured as the amount of heat needed to raise the temperature of 1 liter of water by 1 degree Celsius. Two foods with the same number of calories don’t necessarily affect the body in the same way (e.g., high-sugar foods cause a quick spike in blood sugar, while fiber requires more energy to digest). Alcohol contains “empty calories,” meaning there’s nothing in them that the body can use for energy.

How were calories measured initially? Using a device called a calorimeter, scientists create an isolated environment where heat/energy can’t escape. Then, they apply this formula:

Energy (cal) = mass of water (g) x temperature change (°C)

Note that the energy value of food is typically given in kcal (kilocalories).

1g fat = 9 kcal/g

1g carbohydrates = 4 kcal/g

1g protein = 4 kcal/g

1 ml alcohol = 7 kcal/ml

Now, let’s learn about the two remaining nutrients that are essential for our body.

2. Macronutrients

2.1 Protein

The word protein comes from a Greek word proteios that means “holding first place” because proteins are some of the most important parts of our body. They are the building blocks that make up many parts of us, and they’re a bit different from other nutrients, like fats and carbohydrates. Proteins help create enzymes, which are like little machines that make all the important chemical reactions in our body happen. 

While fats and carbs mostly give us energy or store it for later, proteins are usually used to build things in our body, like muscles, skin, and hair. They can give us energy too if needed, but their main job is to help our body work and grow.

Protein molecules are very large (especially compared to sugar, for example) and consist of many amino acids joined together by peptide bonds in long chains. Due to these many peptide bonds, proteins are also called polypeptides. This may sound familiar from skincare; recently, there’s been a lot of talk about the benefits of polypeptides in skincare. Let’s find out why this could theoretically help and what science is behind polypeptides.

DID YOU KNOW?

Peptides are chains between 2 and 50 amino acids, while proteins (polypeptides) contain more than 50 chains. So, when we talk about skincare or collagen supplements, now we know what we're talking about. Collagen peptides are tiny pieces of protein derived from animal collagen — collagen proteins broken down into smaller amino-acid chains.

Amino acids are mostly composed of hydrogen, carbon, nitrogen, and oxygen. There are 20 different amino acids that are essential for key bodily functions; of these, we can produce 11 ourselves, and the remaining 9 are essential, meaning we must obtain them from our diet as our bodies cannot produce them on their own. (reference)

How are proteins produced in our body?

Think of DNA as a giant instruction manual or a recipe book that lives in almost every cell in your body. DNA is where all the instructions for making proteins are stored, like a cookbook. Each tiny part of DNA, called a gene, gives specific instructions for building a different protein.

Now, when your body needs a particular protein, it finds the right “recipe” in the DNA. A special copy of the instructions is made from the DNA and sent to the ribosome—a tiny factory where proteins are made.

Now, this protein factory doesn’t always work at full speed. It slows down or speeds up depending on what your body needs. It’s careful about when and how many proteins it makes to keep everything balanced.

But, if something goes wrong—like if it makes too many proteins or they come out broken—that can lead to problems. It’s a bit like if a car factory started making cars with missing parts; the cars wouldn’t work well, and people wouldn’t be safe driving them. Similarly, if your body starts making broken proteins, it can make you feel unwell. So, keeping this tiny protein factory running smoothly is really important for staying healthy! (reference)

Where can we find examples of proteins, and what types of proteins are there?
Let’s connect theory with practice!

Types of proteins

DID YOU KNOW?

When we sit down to eat, we only stop feeling hungry after consuming enough protein in a meal. This means that if we want to lose weight, we should eat more protein, as it helps us feel full. However, a high-protein diet from animal sources is beneficial when we’re younger, but as we age, it may have negative health effects—even though we actually need 70% more protein as we get old! (reference) This is due to muscle mass and strength loss, plus older bodies don’t respond to dietary protein as effectively as younger bodies. This information comes from the book The Diet Compass by Bas Kast, which is highly recommended reading.

To reduce health risks associated with animal-based proteins, we should consume more plant-based protein. This is due to something called the “protein package”—not only the proteins we consume are important, but also what comes along with them from specific foods. (For instance, a 113-gram ham steak with 22 grams of protein contains only 1.6 grams of saturated fat, but it’s packed with 1,500 milligrams of sodium.) This is why it matters greatly which types of protein we’re consuming.

Good sources of protein:

• Legumes, nuts, and seeds

• Whole grains

• From animal protein: poultry (chicken, turkey, duck), seafood (high in Omega-3s), and eggs

• Dairy foods—yogurt! Yogurt has huge benefits for gut health.

Not-so-great sources:

• Red meat—reduce intake

• Processed meat—AVOID!
  
  Reference

2.2 Carbohydrate

Carbohydrates are the main source of energy, but they also play a major role in gut health (fiber) and immune function. Let’s learn more about them.

Carbohydrates

The American Heart Association explains that the body processes complex carbohydrates more slowly than simple ones, providing a healthier energy source. (reference)

2.2.1 Glucose

Glucose is the simplest type of carbohydrate that our body uses for energy. When we eat, our body breaks down food into glucose with the help of enzymes, which the pancreas releases. If there’s too much glucose in the blood, the pancreas sends out a hormone (imagine it as a special messenger) called insulin. Insulin helps move glucose from blood into our cells, where they can use it for energy or store it as fat for later. (reference)

DID YOU KNOW?

Sometimes, the body’s cells don’t notice insulin properly, and that’s called insulin resistance. When this happens, too much sugar stays in the blood, and it can't get into the cells to be used for energy. (reference)

How is glucose made in nature?

Process of Photosynthesis

Glucose is produced by plants through a process called photosynthesis. Plants capture light energy with their leaves and absorb water from the soil and carbon dioxide from the air. Within the plant cells, the water molecules are oxidized, releasing oxygen into the air, while the carbon dioxide molecules are reduced, forming glucose, in which the plant stores energy. (reference) Glucose is used by plants for energy and to create other substances, such as:

• Cellulose (builds cell walls) - provides strength and support to plants.

• Starch (stored in seeds and other parts as a food source).

We can't directly digest cellulose due to a lack of the enzyme cellulase, but it has other important functions: it improves digestion and regulates blood sugar. We don’t get energy from cellulose.

Starch is the primary form of stored energy in plants, usually in the roots. That's why the best way to tell if a vegetable is high in starch is to look at where it grows (potatoes – root – are high in starch; carrots, beets, and sweet potatoes as well). We can digest starch and break it down into glucose. The digestion of starch begins in the mouth with the enzyme amylase and continues in the stomach until the starch is broken down into glucose, which then travels through the bloodstream.

2.2.2 Fructose

Fructose is metabolized somewhat differently than glucose, as it does not require insulin. Known as “fruit sugar”, fructose is primarily found in many fruits, as well as in honey, sugar beets, and some vegetables. It is the sweetest naturally occurring carbohydrate, being 1.2 to 1.8 times sweeter than sucrose, and has a low impact on blood sugar levels. Our bodies do not actually need fructose, as we can obtain all necessary energy from glucose, which is our primary energy source. (reference) In high doses, fructose can be toxic to us! (reference)

2.2.3 Galactose

Galactose is found in milk products. When it links with a glucose molecule, it forms lactose.

2.2.4 Maltose

Maltose is formed from two molecules of glucose. It is less sweet than glucose, and due to growing public awareness about the negative health effects of high doses of fructose in food, many food companies are switching to maltose. However, the effects of maltose on our health are not yet well-researched. Maltose can also be produced from starch. (reference)

2.2.5 Glycogen

When your body doesn’t immediately need glucose from the food you eat for energy, it stores the glucose primarily in the muscles and liver as glycogen for later use.

2.2.6 Sucrose

Sucrose is the classic table sugar. It is formed from one molecule of glucose and one molecule of fructose.

2.3 Fat

Types of Fats

We need fats because they are a source of essential fatty acids that our bodies can’t make on their own. These include linoleic and linolenic acids, which are important for brain development and controlling inflammation. Fat also helps the body absorb fat-soluble vitamins (A, D, E, and K), which can only be absorbed with fats. Any fat that isn’t used for energy is stored in our bodies.

DID YOU KNOW?

During exercise, your body initially uses energy from carbohydrates. After about 20 minutes, it starts to draw more energy from fats. (reference)

2.3.1 Unsaturated Fats

Unsaturated fats are generally liquid at room temperature, and they are beneficial for us. They help lower bad cholesterol (LDL) and can potentially increase good cholesterol (HDL). These fats are especially recommended for people with insulin resistance or polycystic ovary syndrome (PCOS) because they reduce the need for insulin, unlike carbohydrates, which can spike insulin levels.

Unsaturated fats come in two types: monounsaturated and polyunsaturated fats.

• Monounsaturated fats are found in olive, peanut, and canola oils, avocados, and nuts such as almonds, hazelnuts, pumpkin seeds, and sesame seeds.

• Polyunsaturated fats provide a good source of Omega-3 fatty acids, which are essential for overall health.

DID YOU KNOW?

Omega-3 fatty acids are a crucial part of cell membranes, helping to provide structure and support communication between cells. They’re also important for eye and brain health, and they help reduce bad cholesterol (LDL) while increasing good cholesterol (HDL). Foods rich in Omega-3s include fatty fish (such as salmon and mackerel), flaxseed, and chia seeds. (reference)

Other sources of polyunsaturated fats include sunflower, corn, soybean, and flaxseed oils, as well as walnuts. (reference)

2.3.2 Saturated Fats

Saturated fats are mostly found in animal products, cheese, ice cream, coconut, coconut oil, palm oil, and palm kernel oil. Although they’re also present in small amounts in some healthy foods like chicken and nuts, it’s best to limit saturated fats to less than 10% of your daily intake. Studies show that eliminating them completely doesn’t provide major health benefits. However, replacing saturated fats with unsaturated fats can positively impact our health. (reference)

2.3.3 Trans Fats: THE MOST HARMFUL

Trans fats are the most dangerous fats and should be avoided completely. The way they’re made is enough reason to avoid them in our diet. Trans fats are created by heating liquid vegetable oils with hydrogen gas and a catalyst (a process known as hydrogenation). The World Health Organization estimates that trans fats cause over 278,000 deaths each year. (reference)

What do trans fats do?

• Increase bad cholesterol (LDL) and decrease good cholesterol (HDL)

• Cause inflammation in the body

• Contribute to insulin resistance

• Harmful even in small amounts – just 2% of daily calories from trans fats increases the risk of coronary heart disease by 23%. (reference)

Industrial trans fats can be found in margarine, vegetable shortening, fried foods, and baked goods like crackers, biscuits, and pies. Street foods and restaurant foods are often made with trans fats as well. Trans fats also naturally occur in small amounts in meat and dairy products from ruminant animals (e.g., cows, sheep, and goats), and both types are equally harmful. (reference)

Why are trans fats used if they’re so harmful?

Trans fats make oils more stable and prevent them from going rancid. They also turn oils into a solid, which allows them to function as margarine or shortening and makes them ideal for fast-food chains because they can be repeatedly heated without breaking down.

If you need to remember just one piece of information from this article, it’s that trans fats should be avoided at all costs. Above all, they are nasty. The point is to watch a few YouTube videos and they will disgust you, and then you’ll really want to never try them again. Education leads to results.

Recommended Macronutrient Intake:

• Protein

  • 10–35% of daily calories should come from protein.

  • General guideline: 0.8g of protein per kg of body weight per day.

• Carbohydrates

  • 45–65% of daily calories should come from carbohydrates.

  • Carbohydrates provide a primary source of energy.

• Polyunsaturated Fats

  • 8–10% of daily calories should come from polyunsaturated fats.

  • Evidence suggests that increasing polyunsaturated fat intake up to 15% of daily calories (in place of saturated fats) can help lower heart disease risk.

• Saturated Fats

  • Less than 10% of daily calories should come from saturated fats, as recommended by the Dietary Guidelines for Americans.

    Source: Harvard Nutrition Source

3. Micronutrients

Types of Micronutrients

Daily Vitamin and Mineral Recommendations

B Vitamins

• B1 (Thiamin):

  • Role: Coenzyme in carbohydrate and branched-chain amino acid metabolism.

  • Food Sources: Enriched and whole grains, legumes, pork.

  • Daily Intake: 1.1 mg (women), 1.2 mg (men).

• B2 (Riboflavin):

  • Role: Coenzyme.

  • Food Sources: Enriched and whole grains, dairy products, leafy greens, beef.

  • Daily Intake: 1.1 mg (women), 1.2 mg (men).

• B3 (Niacin):

  • Role: Coenzyme, supports transfer of NAD and NADP.

  • Food Sources: Enriched and whole grains, high-protein foods (meat, milk, eggs).

  • Daily Intake: 14 mg (women), 16 mg (men).

• B5 (Pantothenic Acid):

  • Role: Fatty acid metabolism.

  • Food Sources: Found widely in foods.

  • Daily Intake: 5 mg.

• B6 (Pyridoxine):

  • Role: Coenzyme for amino acids and glycogen metabolism.

  • Daily Intake: 1.3 mg.

• B7 (Biotin):

  • Food Sources: Egg yolks, soybeans, whole grains.

  • Daily Intake: 30 mcg.

• B9 (Folate):

  • Role: Nucleic acid and amino acid metabolism.

  • Food Sources: Grains, green leafy vegetables, legumes.

  • Daily Intake: 400 mcg; pregnant women should prioritize intake.

• B12 (Cobalamin):

  • Food Sources: Found only in animal products.

  • Daily Intake: 2.4 mcg; older adults may benefit from supplementation.

Vitamin C

• Role: Antioxidant.

• Food Sources: Fruits, vegetables, liver, kidneys.

• Daily Intake: 75 mg (women), 90 mg (men); smokers should consume an additional 35 mg.

Fat-Soluble Vitamins

• Vitamin A (Retinol):

  • Role: Supports vision, cell differentiation, reproduction.

  • Food Sources: Animal products, fruits, and vegetables.

  • Daily Intake: 700 mcg (women), 900 mcg (men).

• Vitamin D:

  • Role: Supports calcium metabolism, cell growth, bone health.

  • Food Sources: Fish oils, some plants; also produced with UV light exposure.

  • Daily Intake: 10-15 mcg.

• Vitamin E:

  • Role: Antioxidant.

  • Food Sources: Vegetable oils, whole grains, nuts, green leafy vegetables.

  • Daily Intake: 15 mg.

• Vitamin K:

  • Role: Essential for protein synthesis.

  • Food Sources: Leafy green vegetables.

  • Daily Intake: 90 mcg (women), 120 mcg (men).

Minerals

• Calcium:

  • Role: Essential for bones and teeth.

  • Food Sources: Dairy, cereals, legumes.

  • Daily Intake: 1000 mg.

• Magnesium:

  • Role: Energy storage, glucose metabolism, bone health, and more.

  • Daily Intake: 400 mg.

• Phosphorus:

  • Role: Important for bones, teeth, DNA/RNA synthesis, cell membranes, energy production.

  • Food Sources: Milk, dairy, meat, poultry; also used as a food additive.

  • Daily Intake: 700 mg.

• Sodium:

  • Role: Muscle function, nerve signaling, blood pH, and water balance.

  • Daily Intake: 700 mg.

• Chloride:

  • Role: Aids in digestion, muscle function, and water balance. Commonly found in salt (NaCl).

  • Daily Intake: 1500 mg.

• Potassium:

  • Role: Critical for muscle contraction.

  • Food Sources: Fruits and vegetables.

  • Daily Intake: 4700 mg.

Trace Minerals

• Iron:

  • Role: Oxygen transport, energy metabolism.

  • Food Sources: Meat, fortified grains, green leafy vegetables; more bioavailable in animal sources.

  • Daily Intake: 8-18 mg.

• Zinc:

  • Role: Structural and functional component in proteins, present in 300+ enzymes.

  • Food Sources: Shellfish, red meat.

  • Daily Intake: 20 mg.

• Copper:

  • Role: Supports zinc function, part of protein structures.

  • Food Sources: Meat, nuts, seeds, chocolate, shellfish.

  • Daily Intake: 1 mg.

• Iodine:

  • Role: Needed for thyroid hormone synthesis.

  • Daily Intake: 150 mcg.

• Selenium:

  • Role: Antioxidant defense, anabolic processes.

  • Food Sources: Brazil nuts are particularly high in selenium.

  • Daily Intake: 55 mcg.

Source

This was a concise overview of the basics of nutrition. Now we have a solid foundation to dive deeper into nutrition topics and start experimenting with healthy recipes. If you'd like to learn more about any specific subject, feel free to reach out to me!