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You eat clean all week, so what’s the harm in trading the turkey burger for a Double Whopper on Friday night? You’ll find it much tougher to get back on the healthy track on Monday because science shows that foods high in saturated fats can impair your good judgment – for up to three days! The study published in The Journal of Clinical Investigation found that short-term exposure to foods like beef, butter, full-fat cheese and milk, which all contain a type of saturated fat called palmitic acid, turns off the pathways in your brain that make you feel full. Your brain essentially gets hit with a cascade of fatty acids that causes resistance to your appetite-suppressing hormones, leptin and insulin. “You end up eating more of these foods, which can lead to weight gain,” says study author Deborah Clegg, PhD, RD. Simply put, you’re not being told by your brain to stop eating. “If you eat a steak today and a pizza the next day, followed by more high-fat foods, do not rely on feeling full the following day!” explains Clegg. “You will feel hungrier, and you won’t stop eating before you get the ‘full’ feeling because your brain has the fats that are blocking you from feeling full.” Scary, yes, but there’s a lot you can do to short circuit this mind-muddling effect.
Look to healthy fat foods as your best pre-emptive strike against weekend cravings. Foods such as natural peanut butter, seafood, nuts and avocados contain oleic acid, an unsaturated fat that several studies have shown have quite the opposite effect of palmatic acid: You feel full faster and stay full longer between meals. A diet rich in healthy fats are also associated with lower risks of heart disease and breast cancer (case in point: The Mediterranean Diet). Going back to the impact on your brain, healthy fats have long been linked to sharpening your mental acuity, allowing you to better focus on your stay-slim efforts at the gym and on your plate.
In sandwiches: Instead of mayo, add a slice or two of avocado or mash it up and use as a spread. Or use hummus, a bean-based spread made with olive oil.
On salads: Nix the cheese and bacon bits and use fixings such as sliced toasted almonds or chopped walnuts.
In cereal: Replace whole milk with soymilk, and top with a tablespoon of almonds.
In stir-fries: avoid using cooking oils that are high in saturated fat and trans fats such as vegetable oil or palm oil; instead use canola or olive oil.
The take-home message is to not rely on feeling full from foods high in saturated fat; instead, count on healthy fats (like in our tasty recipe) to do the trick.