- [Narrator] Maybe you've been pouring skim milk
on your cereal and spritzing non-fat dressing
on your salads for years, but as it turns out,
eating fat won't make you fat.
In fact, research shows that low-fat diets
don't seem to aid in weight loss
or in reducing risk of disease compared to high-fat diets
and all those refined carbs that you've been eating
to replace that fat might be the real issue.
To understand how fat can be healthy,
it's helpful to first understand what's going on
with carbs in your body.
When you eat a simple carbohydrate, like a slice of bread,
enzymes in your saliva immediately start
breaking that food down into sugar.
That surge of sugar triggers a hormone called insulin,
which tells your body to store available energy
in the bloodstream, in fat tissue and in other forms
and the later surge crash makes you feel hungry,
encouraging you to eat more, but fats are another story.
Fat isn't processed the same way as carbs.
It can't be broken down with saliva,
or fully digested by stomach acid.
Instead, your small intestines,
with the aid of bile secreted by your liver, break it down.
This happens much later in the digestive process,
so fat digestion is much slower.
The different fats interact with your hormones
in complex ways that, unlike carbs,
don't cause a massive spike in insulin
and good fats are really important for
your body to function properly.
Monounsaturated fats can be found in olive oil and avocados.
This good fat helps reduce inflammation
and levels of LDL, or bad cholesterol, in the blood.
Polyunsaturated fats in foods like sunflower seeds,
walnuts and fish, also have significant health benefits.
Fish oil, for example, consists of one type
of polyunsaturated fat called Omega-3 fatty acids,
which have been found to decrease blood pressure,
increase HDL, or good cholesterol,
and may also protect against heart disease,
but saturated fats, found in red meat and dairy,
are a different story.
An extensive study found that replacing
a small percentage of calories coming in
from saturated fats with calories from unsaturated fats,
reduce the risk of death, heart disease,
and a number of neurodegenerative diseases.
At the same time, studies show that full-fat dairy
is healthier than reduced-fat diary.
One recent study found that drinking full-fat dairy
was associated with a lower risk of diabetes,
so while unsaturated fats are better,
saturated fats aren't entirely useless.
Not only are unsaturated fats essential for your body,
avoiding them in the name of weight loss
isn't actually a helpful way to shed unwanted pounds.
A study by the Women's Health Initiative
assigned women to low-fat diets for eight years.
They found the participants didn't seem to gain protection
against breast cancer, colorectal cancer,
or cardiovascular disease.
And in the carb versus fat debate,
an extensive 2017 study found no association
between dietary fat and heart disease.
In fact, the researchers found that high carb diets
were linked to a higher risk of death.
So, if studies show that fat doesn't make us fat
or doesn't increase our risk of heart disease
and carbs make us hungry and are linked to
a higher risk of death, should we all
just ditch carbs altogether?
Probably not.
Recent research seems to advocate
a balanced diet that includes a combination
of healthy fats and complex carbs.
Researchers found that diets high in fiber
and low in refined grains, meat and sugars,
resulted in less weight gain.
So what should you eat?
The good news is you can find healthy fats
and complex carbs in a variety of tasty foods.
You can find unsaturated fats in fish,
olives, nuts and seeds and still have a place
on your plate for so-called good carbs.
Although you should probably avoid
eating lots of refined carbs, like white bread and rice.
Foods like sweet potatoes, raw apples
and legumes are a different story.
These foods don't cause the same sudden peaks in blood sugar
and, like healthy fats, they contribute to
a balanced diet to keep your body running.
So go forth and toss some oil on that salad.
(upbeat music)