Preventing disease is the first step to long-term health and well-being. By following basic nutrition advice you can improve your health by significant amounts.

Obesity as a worldwide public health crisis

Western diet is now a major cause of obesity, which is a recognized chronic disease with well-defined health consequences such as Cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, certain types of cancer, osteoarthritis, depression 1. Obesity is labelled by the WHO as a worldwide public health crisis 2. Western diet is normally defined as highly processed foods with very little whole grains, fruits and vegetables. The rate at which obesity is increasing is also increasing at an alarming rate. Data shows that 39% of adults aged 18 years and older were overweight or obese in 20163.

Fig. 1: Obesity is increasing worldwide at an alarming rate. Source

The need to be aware of nutrition in order to avoid obesity and stay healthy now is more than ever. Controlling our food behavior is essential to our long term well being.

Why is obesity increasing?

We are increasingly outsourcing our food preparation. Convenient food has become a norm. These fast-food is often designed as snack-food and marketed to be eaten continuously throughout the day. Such foods are not only less healthy, very high in salt, trans-fat and sugar, but we also tend to overeat them.

This is not an Ad. As seen in the above commercial, nutrient dense foods tend to spoil fast while processed foods usually have very low nutrients in order to increase their shelf life (even pests don’t want to eat processed food). The refining process removes important nutrients such as fiber, iron, B vitamins, in order to increase the food’s shelf life. Their business model is to use the cheapest available raw ingredients, process it as much as possible to increase shelf life and add large amounts salt, fat and sugar to make them seem attractive.

Focus on food rather than nutrients

We have all been taught that food is made up of 3 macronutrients

  • Carbohydrates
  • Proteins
  • Fats

Historically, food was a scarce resource. In the animal kingdom, presence of food was unpredictable. So, we evolved to store food in the body for later use. All calories (including proteins, carbs and fats) that aren’t converted into usable energy, ATP, are stored in the body in the form of adipose tissue for later use. This is what we call body fat. It is not necessarily bad to have body fat but if you have excess of body fat, it can lead to severe long term-health issues.

Is dietary fat really bad?

To address obesity, a lot of focus on reducing saturated fats in diets were made. The processed food industry responded by supplementing fat with sugar to make the food seem more appealing. This also increased the shelf life of foods and so almost every packaged food now comes with enormous amounts of sugar and other sweeteners. This fueled our modern obesity and diabetes.

Despite of an enormous increase in the supply of fat-free foods, obesity rates continued to rise. It is important to know the difference between good and bad fats

The good, the bad, and the ugly

  • Unsaturated fats, such as Omega-3 fatty acids, which are found in fish and some nuts,seeds, are good for long term health. In fact, Omega-3 fatty acids are the only kinds which cannot be made in human body. So, it is essential to have them.

  • Saturated fats are bad for health 4. They increase the amound of bad chelestrol in the blood (LDL).

  • While naturally occurring unsaturated fats, such as the ones found in olive oil, avocado, fish and nuts are good, chemically engineered saturated fats, such as the ones found in margarines and frying oils have week chemical bonds and are easily converted into trans-fats 5. Trans fats increase the amount of bad cholesterol in the blood (LDL) and decreases the amount of good cholesterol (HDL), which increases the risk of heart disease 6. These must be avoided as much as possible.

Are carbohydrates really bad?

A lot of recent focus has been on the fact that we overconsume carbohydrates. A lot of popular diet trends encourage us to drastically reduce carbs from our diet, even to the extend of avoiding fresh fruits and even grains. At the same time, they seem to suggest that high intake of proteins and fats can be eaten freely. But, a diet with high amounts of animal protein and no whole grains, fruits could leave us with serious problems in the long run.

Carbs has a large variety of foods, some of which are very important for our health, such as brown rice, rolled oats which are rich in fiber; and some are are bad for our health, such as corn-syrup, which has no fiber. In general, the lower the glycemic index (GI) of the carbohydrate, the better. A list of low, medium and bad carbs w.r.t GI is mentioned here.

What about proteins?

All proteins are not created equal. Plant based proteins contain more fiber and less saturated fat than animal based proteins. People who eat lots of plant based diet, have much better health and longevity than people who eat heavy meat diet 7. A diet high in poor quality animal protein, such as processed meat, and high fat cuts, can be harmful to health. Processed meats tend to have very high amounts of sodium, which is a contributor to high blood pressure.

Thinking of food as a whole and not as macronutrients

Categorizing foods into these basic micronutrients may be helpful to study foods but it is not helpful to communicate about them. Food is much more complex than just these macronutrients. So, rather than focusing on nutrients, we should focus on food, because ultimately we don’t eat nutrients but food.

Key takeaways:

The quality of the source of nutrients matters a lot for long term health.

  • Eat
    • naturally occurring unsaturated fats, such as avocado, olive oil, nuts
    • low GI carbs with lots of fiber
    • plant-based proteins.
  • Reduce
    • saturated fats, such as red meat
    • medium GI carbs with less fiber
    • animal based proteins.
  • Avoid
    • trans fats, such as oils used for frying in fast food restaurants
    • refined sugar and carbohydrates with high GI
    • processed meats

Exercise 

eating --> energy++
excercizing --> energy--

For people who are trying to lose excess weight, favoring energy expenditure over energy storage needs to be prioritized. This can be achieved by consuming fewer calories and exercising more.

But, not only the quantity of the food, but also the quality of the food we eat matters.

Summary

When we outsource our food preparation to large companies or restaurants, we get low nutrient dense food.

Nutrient density=nutrients per gramcalories per gram\text{Nutrient density} = \frac{\text{nutrients per gram}}{\text{calories per gram}}

Home-made food, cooked using high quality ingredients, having natural unsaturated fats, low GI, lots of fiber, and mostly plant-based protein will lead to good long-term health and longevity. The following food pyramid summaries this in a graphical, easy to remember illustration.

bmi

Fig.3: Food pyramid. Spmallare, CC BY 3.0, via Wikimedia Commons

Even if you’re not obese, being aware of the food you eat and maintaining physical exercise will ensure long term health.

References

  1. https://en.wikipedia.org/wiki/Obesity#Effects_on_health ↩

  2. Hurt RT, Kulisek C, Buchanan LA, McClave SA. The obesity epidemic: challenges, health initiatives, and implications for gastroenterologists. Gastroenterol Hepatol (N Y). 2010;6(12):780-792. ↩

  3. WHO (2018) – Fact sheet – Obesity and overweight. Updated February 2018 ↩

  4. https://en.wikipedia.org/wiki/Fat#Cis_and_trans_fats ↩

  5. https://en.wikipedia.org/wiki/Saturated_fat#Association_with_diseases ↩

  6. https://www.webmd.com/diet/guide/understanding-trans-fats ↩

  7. https://www.health.harvard.edu/blog/eat-more-plants-fewer-animals-2018112915198 ↩