Lessons in Nutrition and Healthy Eating

April 17, 2018



Eating healthy is super important if you want to lead a healthy lifestyle.

A while ago, I really wanted to learn more about the correct way to eat so I decided to take a Stanford University course on the Coursera platform - the Stanford Introduction to Food and Health course.

Since I'm no expert on Nutrition, I thought I'd share my notes and takeaways from the course. 

I thought it was great because it focused on correcting many misconceptions we have about the foods we should eat and avoid, which might surprise you.

If you'd like to know what these are, keep reading!


# 1. CARBS AREN'T THE DEVIL IF THEY CONTAIN FIBER

The first thing I took away from this course was that the idea that we should avoid carbohydrates to be healthy or even to lose weight isn't absolutely correct. 

As a matter of fact, there are carbs that are very valuable to our bodies, like whole grains (e.g. brown rice), since they give us energy but they also have fiber.

The reason why fiber is so important is the fact that it slows the release of glucose (sugar in the foods) into the bloodstream. 

And a slower release of glucose means that there will be a less aggressive response of insulin.

In contrast, eating foods that are high in refined carbs (e.g. white bread or soda) and low on fiber results in a faster release of glucose and, consequently, a more aggressive insulin response, which combats high blood sugar levels.

The ideal thing is maintaining stable blood sugar levels and these spikes in glucose and insulin don't allow for that. In practice, hunger will return sooner and we'll have a tendency to overeat because of the quick hunger return.

Additional Tip: A good way to eat carbs that are low on fiber is to combine it with protein or foods with dietary fat.

# 2. KNOW YOUR PROTEIN

Did you know that there are complete and incomplete sources of protein? I didn't!

So, basically, animal sources of protein (e.g. fish and eggs) are complete protein sources. 

They are complete because they provide all the essential aminoacids in a high concentration.

On the other hand, plant sources of protein (e.g. beans, lentils, nuts, tofu) are usually incomplete sources of protein. 

However, they can be combined with other foods - like seeds, nuts, legumes, vegetables and grains -  to provide a complete profile of aminoacids.

It is also important to remember that plant-based sources of protein usually contain more fiber and less fat than animal protein, which means they are healthier, provided you combine them with those other ingredients we mentioned.

There's also less healthy animal protein...
Red meat is an example of that  it often has a lot of fat (including saturated fat), which can contribute to elevated levels of LDL cholesterol (aka the bad kind of cholesterol).

Then, there's the trouble with processed meats, which are unhealthy for other reasons: they contain preservatives which can damage blood vessels and raise blood pressure, but they tend to be high in salt (or sodium) too, which also has that effect.

In essence, we should moderate the intake of red meat for all these reasons.

 

# 3. THE DEAL WITH FATS

It's important to know the 2 types of fats and how to distinguish them:

  • SATURATED FATS:

    The name of these fats comes from the fact that the fatty acids on these foods are saturated with hydrogen, which, in practice, means that they can lie flat and be packed together densely - that is why they tend to be solid at room temperature.

    These are things like butter, meat, cheese, bacon or lard.

    These foods do increase the bad cholesterol (LDL) but they don't lower the good cholesterol (HDL) either, so they aren't as bad for you as they seem and they don't contribute to arterial plaques as much as trans fats - however, this obviously doesn't mean you should eat loads of it!
  • UNSATURATED FATS:

    As the name indicates, the fatty acids on these foods are less saturated with hydrogen.

    This means they will not pack together as tightly and they are usually liquid at room temperature.
    The deal with this kind of fats is that they have 2 subtypes - one of them is great and the other one isn't so good - as follows:
    • Natural unsaturated fats (e.g. avocado, nuts, olive oil).
    • Man-made unsaturated fats (e.g. margarine, deep-frying oils) - these are the bad kind (also called trans fats).
      They increase the bad cholesterol (LDL), while also decreasing the good cholesterol (HDL), which promotes the formation of arterial plaque, increasing the risk of heart problems.
Note: There is a special type of unsaturated fat which is essential because it contains the only nutrient that the human body needs but can't create for itself - the Omega 3 fatty acids.
These exist in fish oil, nuts, flax seeds and vegetable oils.


# 4. WHY HIGHLY PROCESSED FOODS AREN'T GREAT

The big problem with highly-refined or processed foods is the fact that they suffer the removal of important nutrients, like fiber, iron and B vitamins during this process.

This is because the producers want these foods to have a softer texture and a longer shelf-life. 

Something really interesting and useful to know is that this usually means that foods that last longer tend to be less healthy - they last longer because they are low in nutrients and even the pests (like mold) are less attracted to these foods.

In contrast, healthier foods will have more nutrients per calorie.

That's why foods like fresh spinach are healthier than soda - the first one is high in nutrients in comparison to its caloric content. 

The second one, however, is low in nutrients and high in calories, which happens because nutrient-stripped foods require the addition of sugar, fat and salt to taste good (this is, essentially, what happens with fast food).

Additional tip: How can we find out if a food is highly processed? Look at the ingredients! A food with fewer ingredients is almost certainly less processed. And if the ingredients are too scientific-sounding, that's a sign that it is processed. The best kind of foods don't come with ingredient lists - they are natural!

 

# 5. SUGAR INTAKE 

Apparently, the majority of the sugar we take in doesn't come from sweets or desserts, but from highly processed food and sweetened beverages.

According to the World Health Organization (WHO), we should limit our daily sugar intake to 5-10% of the total amount of calories that we consume in a day.

The average adult should get 2000 calories a day, which means no more than 100 calories of sugar (which is equivalent to more or less 25 grams or 6 teaspoons of sugar).

Note: this doesn't apply to the sugar that is present in whole fruits and vegetables or in milk. 
It only applies to sugars that are added to foods, as well as to sugars that are naturally present in certain foods - e.g. honey, syrups and fruit juices.


You can find a basic summary of all this below:
 


Disclaimer: I have no affiliation with Coursera or with this course. It is completely free for anyone to take.


You Might Also Like

0 comentários

Subscribe