Some dietary components like protein and fiber suppress appetite. Protein does this by activating appetite-suppressing hormones like CCK, while fiber slows down the rate at which food empties from your stomach. That can work in your favor if you’re watching your weight. On the other hand, one type of fat that most people eat every day appears to have the opposite effect. According to a recent study carried out at the University of Texas Southwestern Medical Center, palmitic acid, a type of saturated fat common in beef and dairy products blocks the “full” feeling you get after a meal that keeps you from overeating.
Appetite Hormones and Diet: Another Reason to Watch the Type of Fats You Eat?
Researchers at the University of Texas Southwestern Medical Center recently found that a saturated fatty acid called palmitic acid blocks the fullness-inducing effect of leptin, a key appetite hormone, and insulin. After a meal, leptin levels rise in response to insulin release. As a result of this insulin “signal,” leptin tells your brain that you’re full and you feel the urge to stop munching out. In normal people without leptin resistance, this type of signaling works well for inducing satiety, but palmitic acid appears to alter this response. In rats and likely in humans, palmitic acid blocks the normal insulin-leptin interaction after a meal – and that’s not a good thing when it comes to controlling your appetite.
What is Palmitic Acid?
Palmitic acid is a saturated fat most abundant in beef and dairy foods like cheese, butter and milk. Dairy products have health benefits, but according to this research, they may not be ideal for appetite control. Previous research reached similar conclusions about palmitic acid – it upsets the normal insulin and leptin signaling that turns off the desire to eat. Prior research even points to how it works. It activates a gene called the PKCB gene that alters the normal insulin-leptin response.
Not All Fats Are Bad
The good news? Not all fats send your appetite into overdrive. According to a previous study, olive oil, a good source of monounsaturated fat, didn’t have the same impact on appetite hormones as palmitic acid. In fact, monounsaturated fats abundant in olive oil may have benefits when it comes to weight control. Research shows these “good fats” improve insulin sensitivity and help to keep belly fat in check. Olive oil is one of the best sources of monounsaturated fats, but nuts, avocados, olives and dark chocolate are also good dietary sources of this fat. Other healthy fats are the omega-3 fats in fatty fish. Monounsaturated fats and polyunsaturated omega-3 fats have the added benefit of reducing the risk of heart disease.
What Does This Mean?
Changing the type of fats in your diet could help you keep your appetite in check. Monounsaturated and omega-3 rich polyunsaturated fats from sources like fatty fish, olive oil, avocados, nuts and chocolate are a better choice if you’re trying to control you appetite – and your weight. That doesn’t mean you should give up dairy foods. Dairy foods are an excellent source of calcium and CLA, two dietary components that are important for weight control. One way to get the benefits and still reduce the amount of palmitic acid in your diet is to choose low-fat cheese and dairy products and balance them out by getting more of your daily fat from “good fats” instead.
The Bottom Line?
Don’t be afraid of fat, but make sure a good portion of the fat in your diet comes from monounsaturated fat and omega-3s rather than loading up on foods rich in palmitic acid like beef and full-fat dairy. It’s a small change you can make that could make it easier to control how much you eat as well as your body composition.
Southwestern Medical Center “Ice cream may target the brain before your hips”
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