Fat gets a bad rap these days. There’s a big difference between good fats and bad fats. But, the low fat craze in the 80’s and 90’s led to the false perception that more dietary fat meant more body fat. Unfortunately, lots of folks still believe it.
Guess what? They’re dead wrong.
Before I elaborate, it’s important to understand what fat is and what role it plays in your body. Dietary fat is a macronutrient (along with carbohydrates and protein) that’s a major source of energy for your cells. Your body uses fat to perform several essential functions.
Here are a few:
- Helps absorb vitamins and nutrients
- Acts as an insulator and maintains body temperature
- Improves the taste, aroma, and texture of the food
- Aids in digestion
- Provides essential fatty acids
- Protects internal organs from shock and injury
What are good fats?
So then, what are good fats and what are bad fats? The short answer is: it’s not so black and white. Allow me to elaborate …
The traditional view is that the first two types of fat (mono- and poly-unsaturated) are good fats and saturated and trans fats are bad fats (click the links to read my in-depth articles about these two types of fat). But, new research is starting to emerge that shows foods with certain types of saturated fats may have health benefits.
Let’s explore each type:
Monounsaturated fats are widely considered a healthy type of fat. When you consume monounsaturated fats in moderation, they can help:
- Lower your bad (LDL) cholesterol
- Raise your good (HDL) cholesterol
- Reduce your risk of developing heart disease
- Help protect against certain cancers, like breast cancer and colon cancer
- Provide essential fatty acids for healthy skin and the development of cells
Foods I recommend eating that are high in monounsaturated fats include extra virgin olive oil; avocados; nuts such as almonds, walnuts, and pecans; and seeds such as pumpkin and sesame seeds.
Polyunsaturated fats are found mostly in plant-based foods and oils. Evidence shows that eating certain foods high in polyunsaturated fat can:
- Reduce your risk of cardiovascular disease
- Lower bad (LDL) cholesterol
- Reduce your risk of stroke, heart attacks, and certain types of cancer
However, research also shows there are good and bad types of polyunsaturated fats. That’s because certain types of polyunsaturated fats (mainly highly processed vegetable oils like soybean, corn, safflower, and sunflower) are higher in inflammation-promoting Omega-6 fatty acids, which can lead to major problems in your body (such as increasing your risk of heart disease).
For years, the mainstream nutrition authorities have been telling us to eat more of these types of vegetable oils, and it’s simply wrong. To learn more, check out Chris Kresser’s well researched overview of Omega-3 and Omega-6 fatty acids.
Foods high in polyunsaturated fats I recommend eating include real, whole foods like flaxseeds; fatty fish like tuna and wild salmon; and most nuts. Avoid highly processed vegetable oils like safflower, sunflower, soybean, corn, and sesame oils. Stick with coconut oil and olive oil instead. Speaking of coconut oil …
Saturated fats are a major source of confusion too. While most health organizations for years have said to severely limit your intake of saturated fats, research shows that certain types of saturated fats may actually be beneficial.
Opponents of saturated fat point to dated, flawed research studies that claimed certain saturated fats may raise your LDL (bad) cholesterol. But the largest study ever conducted on saturated fat, that included a meta-analysis of 350,000 people, found no relationship between the intake of saturated fat and the incidence of heart disease or stroke.
If you want to lose weight, I still recommend limiting your intake of saturated fat from dairy simply because it’s high in calories. But my diet includes plenty of coconut oil, raw cocoa powder, and cheese and butter from grass-fed cows. Choose the real, full fat foods over the highly processed junk.
There’s no question that the one type of fat you want to avoid is artery-clogging trans fat. It offers no nutritional benefit and raises your LDL (“bad” blood cholesterol) while also lowering your HDL (“good” blood cholesterol). You’ll find trans fats in foods like French fries and other fried food, donuts, cakes, and other processed dessert foods.
How much fat do you need?
The Institute of Medicine (IOM) established the following “acceptable ranges” for fat intake for adults and children.
Total Fat Intake
|Children (ages 2 to 3)||30% to 40% of total calories|
|Children, teens, and young adults (ages 4 to 18)||25% to 35% of total calories|
|Adults (19 and older)||20% to 35% of total calories|
Here’s my problem with these numbers though: there’s no research to support the “low fat diet” approach.
In fact, an eight-year clinical study, the “Women’s Health Initiative Randomized Controlled Dietary Modification Trial”, which included almost 49,000 women, found virtually identical rates of heart attack, stroke, and other forms of cardiovascular disease in women who followed a low-fat diet and in those women who didn’t. Furthermore, women on the low-fat diet didn’t lose or gain any more weight than women who followed their usual diets.
These results were published in one the most prestigious medical journals in the world, the Journal of American Medicine, in 2006.
And, in a study published in the New England Journal of Medicine, women on low-carbohydrate diets that were high in vegetable sources of fat or protein had a 30 percent lower risk of heart disease and lower risk of developing type 2 diabetes, compared to women on high-carbohydrate, low-fat diets.
Long story short: most people would benefit from eating more good fats (olive oil, fish, nuts, seeds, dark chocolate, grass fed butter and beef) and less carbohydrates.
This article is #5 in my 9-part tutorial called “Healthy Eating 101”.
To go to the next article about healthy fats vs. unhealthy fats click here.
To read article #4 about what types of protein you should eat click here.