or simply spread on toast. Chances are butter has been part of your life and diet.

Or is it margarine? What is the difference between butter and margarine and is one

healthier than the other? Butter, made from cream or milk has been used for

thousands of years. But scientists eventually took notice of its high

levels of saturated fat. With more than 35 calories per teaspoon, butter

is fattening. When we look at the molecules of butter we see some of the

building blocks of life, carbon, hydrogen and oxygen. But these carbon atoms are

completely surrounded by the hydrogen atoms. And this saturation level

quickly became associated with, and commonly believed to contribute to

cardiovascular disease. Margarine on the other hand is created primarily from

plant oils which have a similar but different chemical composition. The

carbons double bond with each other so that fewer hydrogen can fit and we call

this unsaturated fat. So far so good, a similar tasting substitute with less

saturated fat. Right?

Not so fast, unsaturated fat has a lower melting point and so its natural state

is less solid, like vegetable oil.

In order to get the consistency of butter scientists decided to make it a

little more saturated.

The problem is through this process called hydrogenation where more

hydrogen is added and the oil becomes more solid, high temperatures are used

which cause some troublesome changes.

You see, most of these double bonds are in a configuration known as "cis bonds",

but hydrogenation often flips them into something called a "trans configuration".

Ah, the dawn of trans fats.

And while it may seem trivial, this simple yet unwitting flip from "cis" to

"trans"

leads to significant changes in the way our body processes and metabolizes the

molecules. Essentially trans fats lower good cholesterol and higher the bad

cholesterol which increases the risk of coronary heart disease. So while margarine was

initially seen as a healthier option, it's own hazards slowly came to light.

But the truth is that many margarine companies claim to be trans fat-free

nowadays, and some are. At the end of the day if we compare them side by side

there are pros and cons for each. Butter is completely natural and typically made

from one ingredient, whereas margarine is processed and has many ingrediants. Butter

also has some essential vitamins and minerals such as vitamin a and e. But margarines

now vary so much it is difficult to make an accurate comparison. Many hard

stick margarines are still high in trans fats and much worse than butter. But some

newer margarines are much lower in saturated fat, lower their calorie count and

contain zero trans fats. The bottom line is to be aware of what you are eating.

Margarine can vary so drastically that looking at the label to understand what

is or isn't and it will help you make informed decisions.

And there are healthier alternatives to both,

such as vegetable oil spreads or using olive oil to dip your bread instead

of buttering up.

No matter what you choose, the recommended goal is to limit the intake

of saturated fat and avoid trans fats altogether.

This episode of AsapSCIENCE is supported by audible.com, a leading provider of

audiobooks with over one hundred thousand downloadable titles across all

types of literature. If you would like to learn more about food science

I recommend the book "What Einstein Told His Cook" by Robert Wolke.

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