Let’s take a quick look at the fundamentals of nutrients and the history of nutrition.
In order to survive, the human organism needs to take in oxygen, water, and food. You can survive only about three minutes without air, three days without water, and three weeks without food.
Because food is so important to our survival, it’s been studied extensively and since 1827, when a British physician by the name of William Prout first proposed that humans needed three macronutrients to survive.
How many nutrients do you need to optimize your health?
According to a research published by the Harvard Medical School, good nutrition, and the way in which in our bodies absorb and process nutrients is a much bigger puzzle than a nutrient-by-nutrient tally sheet suggests.
Most nutrients don’t fly solo: they interact, join forces, cancel each other, jockey for position on metabolic pathways.
Physicians, scientists and increasingly the general public have been trying to figure out exactly how much of each of these nutrients will optimize your health.
To some extent, the focus on nutrients rather than food has confused many people.
There is a little bit of confusion around nutrients
And people tend to get lost in this conversation about which nutrients are good or bad, and it’s understandable, because scientists need to reduce things to a single variable to study them, and the variable in food would appear to be the nutrient.
But people also have lots of studies that show that simply removing or boosting nutrients or turning them into supplements doesn’t seem to work, that food is much more complicated, it’s a system.
What is a basic understanding of nutrients?
A basic understanding of the nutrients can give you a helpful background for your discussions about food.
So you’ll review the nutrients and how the body uses them. Ultimately people eat food, not nutrients.
The whole spectrum of carbohydrates go from whole-grain to white bread
All nutrients are not created equal, especially when it comes to their effect on your health.
So, changing the focus of the discussion from nutrients to foods, can more effectively to help you to develop eating habits that will support your long-term health.
By speaking about nutrients rather than food, you can end up conveying the wrong message; in recent years, a great deal of scientific and media attention has been focused on the excessive amounts of carbohydrates in the average Western diet.
You will encounter many popular diet trends that encourage you to drastically reduce the carbohydrates in your diet, while you are given the message that you can eat protein-rich foods of any kind freely.
This doesn’t usually lead to a diet that will be healthy for you in the long run.
Not all carbohydrates need to be held in contempt of the average healthy person’s diet.
Whole grains, like brown rice and rolled oats, are carbohydrates that provide your body with a useable source of energy.
Bound together in that very same food, is a significant amount of fiber, which modulates the release of glucose from that food into the bloodstream.
In a prospective study of 9,494 male Israeli government employees who were nondiabetic and 40 years of age or older at baseline, found no association between calories from sugars or intake of total carbohydrates and incidence of diabetes mellitus over a 5-year follow-up.
In a cross-sectional study of 3,454 employed people in England, observed that the intake of carbohydrates, fats, and protein tended to be inversely correlated with the concentration of blood sugar and indices of glucose tolerance.
They inferred that the correlations probably were confounded by caloric expenditure, according to a research published by the NCBI.
Explaining the glycemic index
The glycemic index of a food is a measure of the speed at which glucose is released into the bloodstream after it’s digested.
A whole grain, like brown rice or quinoa, will result in a slower release of glucose and a more muted insulin response.
On the other hand, a food that’s high in refined carbohydrates, like white bread or soda, will lead to a more rapid release of glucose into the blood and this is likely to cause a reactive spike in insulin.
Because spikes of glucose and insulin lead to less stable blood sugar levels, eating foods that are refined, especially highly processed carbohydrates, can result in an earlier return of hunger and a tendency to overeat.
The glycemic index of a food is lowered when the food contains fiber or when the food is consumed in combination with protein-rich foods or other foods containing dietary fat.
Low glycemic index foods help to manage blood sugar levels
For people who are struggling to manage excess weight or elevated blood sugar levels associated with diabetes, eating foods that have a low glycemic index is especially important, but even healthy individuals will benefit from choosing low glycemic foods.
So, when you speak about dietary carbohydrates, you are actually speaking about a very broad family of foods.
Some that can be harmful to your long-term health and some that can support it.
What are carbohydrates?
Carbohydrates are broken down and converted to glucose which can then be metabolized by the body to produce usable energy in the form of ATP.
If energy demands are low, glucose can be stored and most of the time it’s stored as adipose tissue.
1. Dietary carbohydrates
Dietary carbohydrates are combinations of sugar units that come in both simple and complex forms.
2. Simple carbohydrates
Simple carbohydrates include the monosaccharides or single sugar units, like glucose and fructose as well as the disaccharides or two sugar units like sucrose or table sugar.
3. Complex carbohydrates
Complex carbohydrates or polysaccharides include the dietary starches that our body can break down and digest and also the indigestible polysaccharide that makeup dietary fiber during the process of digestion.
Plant & animal proteins are the building blocks of the body
Protein-rich foods, including animal and plant-based proteins, can also vary enormously in their quality and their implications for your long-term health.
Proteins are often said to act as building blocks for the lean tissues in your body.
But they serve many other important functions in body regulation, support of immune function and a variety of other roles in your physiology.
There are 20 types of amino acids needed to fulfill all of these functions, but only 9 of them are essential.
Meaning that your body can’t make enough of them, so you rely on getting these from your food.
What are complete protein sources?
In general, animal sources of protein, like fish and eggs, provide all of the essential amino acids in high enough concentrations that these foods are called complete protein sources.
In contrast, plant-based protein sources, like beans, lentils, nuts, and tofu, tend to be incomplete sources of protein.
It might seem that, since plant-based proteins are incomplete in their nutrient content, that they’re nutritionally inferior compared with animal-based proteins.
But in fact, the health benefits of substituting plant-based proteins for animal-based ones, ideally a few days a week, far outweigh the risk of falling short on essential amino acids.
Plant-based proteins can be combined with other foods to provide a complete amino acid profile
In fact, many traditional food combinations, like rice and lentils or corn and black beans, are based on the principle of combining complementary proteins.
These meals also contain valuable fiber and they’re likely to be lower in fat, especially saturated fat, than a meal that features animal protein.
Research conducted at the Harvard Chan School of Public Health has found that eating even small amounts of red meat, especially processed red meat, on a regular basis is linked to an increased risk of heart disease and stroke, and the risk of dying from cardiovascular disease or any other cause.
Conversely, replacing red and processed red meat with healthy protein sources such as beans, soy foods, nuts, fish, or poultry seems to reduce these risks.
So, when people are on low-carb, high protein diets, it’s important to ask what kinds of proteins are being consumed and in what quantities.
A poor-quality animal protein diet can harm your health
A diet high in animal protein, especially if it’s poor-quality animal protein like processed meat or high-fat cuts of meat, can be harmful to your health.
Processed meats often contain nitrates, used as a preservative, which can damage blood vessels and contribute to atherosclerosis.
These meats also tend to be very high in sodium which can be a contributor to hypertension.
The simplest advice is to choose moderate amounts of high-quality protein-rich foods from a variety of different sources, including some fish if possible as well as vegetarian sources of protein that are combined for completeness.
In 2016, researchers from the JAMA International Medicine reviewed protein intakes of more than 131,000 women and men from the Nurses’ Health Study and Health Professionals Follow-up Study.
After tracking their diets for up to 32 years, the authors found that a higher intake of red meat, especially processed versions (sausage, bacon, hot dogs, salami), was linked to a modestly higher risk of death, while a higher protein intake from plant foods carried a lower risk.
Oversimplified, nutrient-focused dietary advice, like diets that encourage patients to eliminate all carbohydrates, including whole grains, while they consume as much protein as they want regardless of the quality.
These diets almost never lead to sustainable, long-term health.
The human body is a complex organism that depends on interrelated systems working together within tightly regulated parameters.
One of the best ways to protect a system like this is to provide it with the dietary complexity you get from a well-balanced meal, that includes a variety of whole foods.
What are the dietary proteins?
Dietary proteins are also broken down into their component parts, amino acids, during the process of digestion.
These amino acids can be used to build and repair lean tissues in the body and perform many other important functions.
What are amino acids?
Amino acids can also be broken down and used for energy and if they’re consumed in excess they can contribute to fat stores in the body as well.
What are dietary fats and what is their recommended intake?
For decades, the relationship between dietary fats and health was at the center of the attempts to understand the underlying cause of the obesity epidemic.
Despite the important roles that fats play in your body, this entire category of macronutrient was shunned for much of the 20th century.
This led to an enormous increase in the availability of fat-free and reduced-fat foods, but despite this, obesity rates continued to rise.
Proper nutrition offers one of the most effective and least costly ways to decrease the burden of many diseases and their associated risk factors, including obesity, according to a study published by the Oxford Academic.
Good fats vs bad fats
Today, raising awareness about the difference between what some people call “good fats” and “bad fats” have allowed this important part of your food supply to make a comeback.
But once again, the pendulum threatens to swing too far in the opposite direction.
Dietary fats can be divided into two families: the saturated and the unsaturated fats.
1. Saturated fats
Saturated fats get their name from the fact that their fatty acids are saturated with hydrogen molecules.
This means that they can lie flat and pack together densely so that saturated fats tend to be solids at room temperature.
Animal fats like lard and butter are good examples.
2. Unsaturated fats
In contrast, the fatty acids that make up unsaturated fats are kinked in places where double bonds between the carbon atoms cause the chains to be less saturated with hydrogen.
This also means that these fatty acids don’t pack together as tightly, leaving most unsaturated fats in the liquid state at room temperature.
But unsaturated fats can be naturally occurring, like the fats found in olive oil, nuts, and avocados… or they can be man-made, (or chemically manipulated) to become unsaturated.
These are the fats found in some kinds of margarine and in the kinds of oils that are often used for repeated cooling and re-heating in deep frying machines, like the ones used in many fast-food restaurants.
The problem with chemically engineered unsaturated fats is that the chemical bonds between the carbon atoms are less stable.
So they easily flip into a trans orientation rather than a cis orientation, and this is where it gets the name trans fats.
3. Trans fats
Trans fats are problematic for your health because they increase the amount of LDL cholesterol in the blood and by doing this, they promote the formation of arterial plaques.
At the same time, trans fats reduce the amount of HDL, the protective form of cholesterol, in your blood and the result is a greatly increased risk of atherosclerosis and heart disease.
While saturated fats have also been shown to contribute to increases in LDL cholesterol, they haven’t been shown to lower HDL cholesterol or to contribute to the development of arterial plaques as significantly as trans fats.
The best recommendation possible is to enjoy a balanced diet
Probably the most sensible food recommendation that results from the accumulated scientific studies of dietary fats is this.
Enjoy reasonable amounts of foods that contain mostly naturally occurring unsaturated fats, like those found in olive oil, nuts, and avocados.
Avoid all foods containing trans fats, and limit your intake of foods, like red meats, that are high in saturated fats.
How do fats work?
Fats are the most energy-dense storage form providing nine calories of energy for every gram, alcohol provides seven calories per gram.
In contrast carbohydrates and proteins provide only four calories per gram.
How do dietary fats work?
Dietary fats can also be broken down into smaller components and used for energy or they can be stored as adipose tissue depending on your energy needs.
What is the physiologic cause of overweight and obesity?
This is one of the reasons people have evolved to store excess nutrients as adipose tissue and this brings you to the underlying physiologic cause of overweight and obesity.
Any calories that aren’t converted into usable energy in the form of ATP are stored in the body for later use, most of the time they’re stored as adipose tissue.
What do we mean with ‘favor energy expenditure’?
Disturbing the energy balance to favor energy expenditure over energy storage, needs to be one of the priorities for people who are trying to lose excess weight.
This can be achieved by consuming fewer calories, burning more calories through exercise or a combination of both.