A dietitian's four favorite foods that are high in good fats

Body: 

Remember when we used to think that dietary fat was bad? We believed that "fat makes you fat," but now know that obesity is more complex than just overeating a single nutrient. It's amazing how much research now exists on the benefits of fat. It can help quell inflammation, assist with weight control and protect against heart disease, diabetes and cognitive decline.

But before you dive headfirst into a vat of lard, recognize that the type of fat you choose matters. Your best bets are foods that are high in monounsaturated and omega-3 polyunsaturated fats — especially when these foods replace items that are high in trans fat or sugar.

You can get more of these beneficial fats in your diet by adding fish, nuts, seeds, oil and avocado to your meals. Here are four of my favorite fat-rich foods:

Almonds

A one-ounce serving of almonds (¼ cup) has six grams of protein, 13 grams of "good" monounsaturated fat, and is a source of fiber, vitamin E and magnesium. Almonds are a perfect snack, especially when they replace less nutritious alternatives like chips or pastries. This was highlighted in a recent study published in the Journal of Nutrition.

In a randomized controlled trial, researchers compared adults who snacked daily on 1.5 ounces of almonds or one banana muffin (both snacks had the same number of calories).

"The group that snacked on almonds had lower LDL (bad) cholesterol levels, but elevated levels of good alpha-1 HDL cholesterol," explains Penny Kris-Etherton, one of the researchers. Alpha-1 HDL is the form of cholesterol that's known to be most protective against heart disease. So snack on a handful of almonds, or sprinkle them on salad, soup or yogurt.

Avocado

I'm head over heels for this unctuous, silky fruit (yup, technically it's a very large berry). In addition to being high in fiber and monounsaturated fat, avocados also contain lutein, a plant pigment that provides their greenish-yellow hue.

In a recent study, Elizabeth Johnson and colleagues at Tufts University looked at how lutein in avocado can positively affect cognition in older adults. They compared adults aged 50-plus whose diets included one avocado per day vs. a control group, and learned that avocado eaters had increased lutein levels, significantly improved memory and better problem-solving skills.

"Higher levels of lutein are related to better visual and cognitive function," Johnson says.

And while there's lutein in leafy greens too, it isn't as well-absorbed by the body because greens contain little fat. "The monounsaturated fat in avocados increases absorption of fat-soluble lutein, and it positively influences lutein's transport into tissue," explains Johnson.

Add cubed avocado to salad or atop chili; blend it into soups and smoothies; or dip into some guacamole. Avocado oil is great too.

Olive oil

This liquid gold is a staple in most kitchens, and for good reason. Filled with monounsaturated fats, it's recommended for heart health. In fact, consuming three tablespoons of olive oil per day has been shown to reduce the risk of developing heart disease by 37 percent.

It has also been linked to fighting inflammation, assisting with better cholesterol and blood pressure levels, and helping with weight maintenance (that's right, folks, fat doesn't make you fat).

Another perk: Olive oil helps your body absorb the fat-soluble vitamins and antioxidants in vegetables, so it's a perfect salad dressing ingredient.

Chia seeds

About 65 percent of the fat in chia seeds is an omega-3 fat called alpha linolenic acid. It's an essential fat that we need to get from food because the body cannot make it. Chia is the highest food source of omega-3 fat.

Research shows that the omega-3 fats from fish have the strongest health benefit, but the plant-based ones have some potential too. Alpha linolenic acid may protect the brain against strokes, and is associated with a reduced risk of heart disease. Studies on chia seeds show that they can help reduce blood pressure, control appetite and regulate blood sugar.

These interesting seeds soak up liquid to form a gel, so they're a great addition to oatmeal, yogurt or pudding. They can be used as an egg replacer in baking, or to thicken soups and gravies.

In addition to their stellar health benefits, these fatty foods have another bonus — they enhance the flavor of your meals. Yep, fat carries flavor (dry toast, anyone? No?) and adds mouth feel. I love when something that tastes great is also good for you.

But remember, researchers use high amounts of fatty foods in their studies. You're not part of a clinical trial and do not need to consume these amounts. If you add a whole avocado and three tablespoons of oil to your daily diet, you'll get too many calories. So be practical. When you have salad, make the dressing with olive oil. Use avocado instead of butter on your sandwich. Snack on almonds rather than chips. Small changes add up to a healthier overall diet.