The world of nutrition can be very vague with new information constantly bombarding you through social media, news and various other channels. Your friends, co-workers and family want you to eat a certain way. The reality is, eating is one of the most intuitive and simple things humans have been doing for millions of years. With our guides and plans, we will make this a very simple transition for you to kickstart your healthy lifestyle. In this guide, we will talk about some of the very basic concepts of food and nutrition. We will use simple concepts to explain to you concepts that are backed by concrete food and nutrition science while being checked by our in-house research team. All our guides and plans are regularly updated based on what we learn. Without, further ado, welcome aboard!
2. What is Food?
Food is something we eat using our mouth that is processed by our body to be used as a fuel or building blocks. Foods consist of various substances and chemicals that can serve as nutrients which sustain us or compounds that make the foods smell or taste good so that we are lured to eating them. By understanding these different components in foods, we can not only understand how they keep us healthy but also allow us to create new types of foods so that food can not only be a source of sustenance but give us long term joy and wonderful experiences too! Let us look at these components one at a time.
Foods are made up of three major components that can influence our health and well being: Macronutrients, Micronutrients & Periperals
Macronutrients are the essential building blocks and energy carriers for the body. Without them, our body can quickly wither away and are critical to our living and health. You need plenty of these to stay healthy and nourished. There are three different types of macronutrients: Proteins, Carbohydrates and Fats.
They form the building blocks of the body. During the day, body takes wear and tear and needs to be repaired. Proteins help with this process while serving as raw materials for creating new muscles. They can come from plant and animal sources where plant protein are incomplete while animal proteins are complete sources of essential amino acids.
Though proteins can be potentially used by the body as fuel, the body utilizes either fats or carbohydrates as the main fuel sources.
Carbohydrates are molecules that can be used as fuels by turning into simple sugars that can be used as fuel for the body.
Main sources of carbohydrates are sugars, starches, grains, vegetables and fruits but they also also exist in smaller quantities in nuts. Trace amounts can be found in animal products as well.
Fats are another source of fuel for the body and are prioritized to be burnt when consumption of carbohydrates is restricted or totally removed. These fats are converted into Ketone bodies which are further used to fuel the body.
Fats are primarily found in animal products, nuts and seeds. They can be further extracted to make butters, ghee, tallow and various oils.
Micronutrients are essential substances that are required in trace amounts to help regulate several processes in our body and to maintain adequate health. They are equally as critical for health though their requirements are far lower. Due to their importance, there is a Recommended Daily Allowance(RDA) for these micronutrients. There are two types of micronutrients: vitamins and minerals.
Vitamins are organic compounds made by plants and animals which break down in the body to help regulate and enable many processes such as production and release of energy in the body and cell formation and brain function. They can be found in both plants and animals such as meats, fish, dairy, fruits, beans and grains.Vitamins are either water-soluble or fat-soluble. Water soluble vitamins are flushed and need to be replenished while fat soluble vitamins are taken up and used in the body for various processes.
Minerals are inorganic compounds that have several roles in the body depending on the type of mineral ranging from growth, healing, immune function, protection against oxidative damage, creation of hormones and so on.
Food is made up of more than just macronutrients and micronutreints. All of these different components and nutrients add up to create the architecture of food which can control how nutrients are delivered and at what rate. This is an important concept that isn't talked about much but is critical to understanding how food can impact our health and well being.
Fibers are part of plants and can be either soluble or insoluble. They give plants their rigid structure and can slow down or prevent nutrients from being digested in the body by binding around them.
Soluble fibers dissolve in water while insoluble fiber does not and is fermented by the bacteria in our intestines. Both are tolerable and may be useful in small amounts.
FLAVOR, COLOR & AROMA
Food flavors can be either sweet, umami, salty, sour, spicy or bitter. Each of these are mainly detected by our tongue when foods are eaten. They can make foods more joyful and palatable or can make them repulsive!
Aromas are what add a blissful or repulsive smell to foods depending on what is added to the food or whether the food is in the process of decaying. Everyone wants something that smells good!
Coloring agents are naturally existing compounds or synthesized to give the food a more vibrant and attractive look.
Food texture, though outside the scope of this beginner's guide, is critically important as it can be a gauge of how nutrients are digested and delivered in the body. Texture is a cumulative combination of nutrients, fibers, binding agents, flavors and aromatics all-in-one and hence plays a key role in health and nutrition.
Binding agents are components of foods that can change the flow, mouthfeel, texture and rate at which nutrients are absorbed by the body. Some of them can turn liquids into gels while serving as a "glue" for other food components.
They can be found within intact farmed foods and are used in recipes or foods to modify the texture of the food. As they can influence texture, they play a key role in health and nutrition as well.
These are non-nutritive compounds that can have a stimulatory impact on the body while having an indirect impact of health and well being. This includes compounds such as caffeine in coffee which can have an excitatory and theobromine in cocoa which can have a relaxing effect. These compounds are either part of the food itself or added to foods to create the desired effect.
These are usually compounds obtained from natural sources or synthesized that increase the shelf life of products. These compounds are normally rigorously tested for their toxicology before they are allowed to be added to foods.
6. How Food is Digested
After smelling and touching food, the first step in processing food in the body begins in the mouth. Food is first broken down into small pieces in the mouth by our teeth while the digestive fluids in the mouth start reacting with the nutrients to start converting them into something that can be absorbed by our body. Once the food reaches a specific size, it passes down to the stomach.
Inside the stomach, digestive fluids, along with stomach acid, further break down the food chemically while the stomach contracts and expands in a wave-like motion to mechanically break down the food. Once the food becomes extremely small particles or dissolves in the digestive mixture called "chime", it passes to the small intestines.
Within the small intestines, the food is exposed to an alkaline environment where it continues to react chemically with digestive fluids and eventually nutrients are extracted and absorbed into the blood stream for transportation to the rest of the body. Food components such as insoluble fibers are passed into the small intestines and eventually secreted along with other bacterial waste.
7. Animal Food Sources
Animal based foods are usually derived from animal agriculture ranging from various types of animals such as cows, pigs, chicken, ruminants and fish. Inedible parts such as shells, skin and bones are removed and potentially used in other industries while the edible parts are further processed to make them safer and more digestible. Animal based foods are usually higher on fats and proteins with low amount of carbohydrates.
Meat is extracted from animals after inedible parts such as skin and bones are removed and further cooked or processed. These are foods which are usually an excellent sources of fats and proteins while providing a good source of micronutrients packaged with an umami flavor and in a fibrous gel network. They contain trace amounts of carbohydrates and fibers and usually need to be processed or cooked before being eaten.
Eg. Beef, chicken, ham, pork, bacon, sausage, jerky, biltong, salmon
Dairy is a by-product of animal and provide an excellent source of fats and proteins with some carbohydrates and good source of micronutrients. In its raw farm, it consists of milk but is further processed to make semi-solid foods such as cheese.
Eg.Cheese, milk, butter, ghee,
Fish is found in either salt water or freshwater and is usually a good source of proteins and micronutrients. Bigger bones are removed and they are usually consumed cooked.
Eg.Salmon, trout, catfish, crabs, lobsters, prawns, shrimp, caviar, cod, herring
Eggs are obtained from birds and are a high quality source of fat and protein. They are usually cooked prior to consumption.
Eg. Chicken eggs, duck eggs
8. Plant-Based Food Sources
These consist of foods that are obtained from edible plants.
Tubers are rich in carbohydrates with large plant structures that usually need to be cooked prior to consumption.
Eg. Potatoes, sweet potato, cassava, dahlia
GRAINS & CEREALS
These contain high amount of readily digested carbohydrates with minimal proteins and serve as staple foods in many cultures. They can be eaten raw, boiled, steamed or ground,
Eg. Rice, barley, millet,flour, oats, malt, wheat, whole grain, rye, sorghum,
NUTS & SEEDS
Nuts and seeds contain fats, carbohydrates and proteins and have a crunchy texture. They also contain substantial amount of fiber and an overall great addition to any diet while being extremely tasty and packed with micronutrients as well.
Eg. Almonds, pecans, pine nuts, walnuts, chia seeds, sunflower seeds, hazelnuts, macadamias
Vegetables contain all sorts of edible plants that are usually lower in macronutrients but rich in micronutrients and fibers. They can be further processed(eg. cooking, grinding) to improve their flavor, texture, taste and aroma and nutrients available for digestion.
Eg. Carrots, eggplants, kale, spinach, onions, cabbage, broccoli, cauliflower
These are sweet and sour sources of carbohydrates and sugars with a decent source of fibers that are usually consumed raw.
Eg. Apples, oranges, watermelon, cocoa, coffee, grapes, avocado,banana, pumpkin,
These come from a family of pea plants that are carbohydrate and fiber rich with some protein in them.They may be eaten raw or cooking may be required to make them fit for human consumption.
Eg. Peals, lentils, clover, alfalfa, soybean, peanuts, mesquite, tofu
These are fleshy foods that contain very few macronutrients and some micronutrients. Though fungi and mushrooms found in commercial markets are safe to eat, many found in the wild can be poisonous!
Eg. Edible mushrooms
9. Processed Foods
Technically, all foods are processed to some extent. What matters is what is processed, how it's processed and above all, what you get at the end of the processing. Food processing allows us to make foods edible, palatable, digestible and improve their shelf life. This is very important to understand in the context of the modern world especially they can either be some of the healthiest and safest foods to eat while at the same time can be the most detrimental to your health goals. Sometimes, these processes are combined. Here's some of the important ones:
Heating includes cooking, baking, grilling, sous vide, boiling, microwaving and various other methods that cause drastic chemical changes to food which can completely alter the physical appearance of foods.
Eg. Baked goods, breads, soy milk, low calorie foods, condiments, desserts, dumplings, pies, sauces, soups, stews, pizza, chips
Drying involves removal of water from the food which prevents bacterial growth or allows food to be used as an ingredient in another recipe.
Eg. Dried fruits, biltong, jerky, dried meats, popcorn, freeze-dried ice-cream, instant coffee, instant soup, powdered milk
MILLING & GRINDING
Mechanical processing of foods can disrupt plant cell walls and yield more nutrients for our body to absorb while it can yield favorable texture in animal foods.
Eg. smoothie, nut butters, processed meats, minced beef, no-bake desserts, wheat, coffee, cocoa, cereals, chocolate
Foods can be preserved in many ways from basic additives like salt, sugar and modern additives such as ascorbic acid(Vitamin C), nitrates and anti-oxidants to advanced methods such as jellying and pickling.
Eg. pickles, jam, packaged cookies, bacon, sausages
REFRIGERATION & FREEZING
Exposing food to colder temperature reduces bacterial growth and decay. This is especially helpful in preserving foods that have high water content such as vegetables and meats.
Eg. frozen meats, frozen vegetables, perishable foods, butter, yogurt
CANNING & SEALING
This involves keeping food in an airtight container which prevents it from damage from the environment, moisture and sunlight.
Eg. Food bars, packaged foods, canned foods, ghee, jams, nut butters, tea, coffee, chocolate
Fermentation is a complex process which uses bacteria to break down a substance to change its chemical composition.
Eg. Kimchi, kefir, tempeh, cheese, sourdough, yogurt, kombucha, sauerkraut, miso
Food is exposed to boiling water and then removed after a short, timed interval. Then it is placed under cold water cooled quickly to stop the cooking process. This helps reduce quality loss of food while also reducing inhibitory and toxicological components of foods and loosening skin of the food.
Eg. Green beans, nuts, tomatoes, peaches, potatoes
When food is mixed in water, this is called hydrolyzing and this can have a drastic impact on how it can pass through your gastrointestinal tract and get absorbed by your body.
Eg. Sugary drinks, protein shakes, lemonade, cocktails, fat waters
ISOLATING & REFINING
Removing all impurities, other nutritional and non-nutritional components of foods and isolating a certain compound is refining or isolating.
Eg. White & brown sugar, oils, protein powders, starch powders, white flours, added sources of fibers
These foods are chemically and physically identical to farmed versions but made synthetically through an alternative method.
Eg. Sweeteners, Lab grown meat, cell cultured foods, soy milk,
10. Calories & Energy Balance
Our body can be thought of as an energy processing machine. It takes food, breaks it down into nutrients and uses those to rebuild itself after wear and tear or perform physical tasks inside and outside it. In other words, you can think of it as energy coming from food and then energy expended out. If the energy expended is equal to the energy entering the body, the body is in a state of "energy balance". Energy is measured in science using "joules" or "calories" similar to how distance is measured in miles or kilometers and temperature is measured in Celsius or kelvins. One calorie is the amount of energy needed to raise temperature of one gram of water by one degrees Celsius. This is why many foods that you buy at a grocery store have caloric values written on the label. Though the labels may have some discrepancy and measurements in calories can be flawed, the laws of physics and energy are always true. The body is, however, complicated when it comes to using and expending energy so many factors come into play when it comes to fat loss and fat gain which is why focusing mainly on calories alone is not a smart idea!