This story has been updated since it was originally posted on 12/28/2022 to include more items
As we age, our metabolism tends to slow down, making it more difficult to maintain a healthy weight and process the nutrients from our food that help our bodies thrive at their full potential. This is due to a number of factors, including a decrease in muscle mass, hormonal changes, and lower physical activity levels. Luckily, though, there are a few factors that can affect our metabolism that are very much in our control–including our diets. By avoiding processed foods and instead focusing on whole foods, it’s possible to support a faster metabolism and stay fit over time.
Processed foods have become a staple in many people’s diets. Unfortunately, though, these types of foods can take a serious toll on your metabolism in the long run, which is just one reason you should avoid them as much as possible, especially if you want to lose weight or simply avoid weight gain as you age.
To learn more about the effects of these foods and discover some of the worst options out there, we spoke to Jesse Feder, RDN, CPT at My Chrons and Colitis Team, certified weight loss coach Joanna Wen, founder of Spices & Greens, and Emily Johnson, RD, nutritionist from Juicereport. They pointed out sugary cereal, fast food, frozen dinner, potato chips, and processed meats as some of the worst culprits when it comes to your metabolism. Learn more below!
1. Sugary cereal
As delicious and convenient as they can be, sugary cereals are one processed food that can have negative impacts on your metabolism, according to Feder. "Sugary cereals are one of the most unhealthy processed foods you can have. They are loaded with sugar, sodium, and refined carbohydrates," he says. "These things, when eaten in high amounts and consistently, can lead to obesity, high blood pressure, diabetes, and heart disease. The highly processed and refined ingredients typically give you a jolt of energy since they are able to be digested very quickly. This then causes a crash in our blood sugar, and can slow your metabolism." Yikes!
The high amount of added sugars in this food, in particular, poses a whole range of health risks, including weight gain. When we consume too much sugar, our bodies produce insulin to help process it. This insulin surge can cause our cells to become resistant to the hormone, leading to higher levels of insulin in the bloodstream. High levels of insulin can lead to weight gain, especially around the abdominal area, and have been linked to an increased risk of developing type 2 diabetes and other metabolic disorders. Overall, it’s better to cook yourself a nutritious, balanced breakfast–although it may take more time than pouring cereal and milk into a bowl, it’ll be worth it in the end!
2. Fast Food
Despite the fact that it’s an extremely convenient option when you’re on the road, Feder warns that fast food can also ruin your metabolism over time. "Fast food meals are made with high amounts of fat, sodium, and unhealthy oils. This can also lead to weight gain, obesity, cardiovascular disease, heart disease, and stroke to name a few things," he says. "The ingredients in fast food meals are also highly processed and refined which can be digested quickly and leave you with a decreased metabolism."
Fast foods, along with many other processed foods, are often high in unhealthy fats, such as trans fats and saturated fats. These types of fats can increase cholesterol levels and contribute to the development of heart disease and other health problems. They can also cause inflammation in the body, which has been linked to a range of health issues, including obesity and metabolic disorders. Of course, desperate times call for desperate measures–and one McDonald’s hamburger won’t kill you. But whenever possible, go with healthier options, like a salad with dressing on the side.
3. Frozen dinners
Feder says that frozen dinners are some of the worst options out there when it comes to metabolism-slowing processed foods. This is largely due to their high levels of fat and salt. "Frozen dinners typically have large amounts of fat and salt in them to make them taste good as well as keep them preserved. High amounts of fat and salt can lead to weight gain, obesity, high blood pressure, and cardiovascular disease," he explains.
Another problem with this processed food (along with most others) is that it is often low in nutrients and high in empty calories. This means that it provides very few (if any) vitamins, minerals, and other nutrients that our bodies need to function properly. Instead, it’s packed with fillers and additives that have no nutritional value, but can still contribute to weight gain and other health problems. You can still reap the benefits and ease of frozen foods by freezing your own homemade meals to eat later on–but overall, it’s best to steer clear of store-bought varieties.
4. Potato Chips
Potato chips are perhaps the most infamous snack around. They're perfectly salty, crispy, and, unfortunately, loaded with fat. That's why Wen recommends staying away from this crunchy treat if you're trying to slim down. "Many chips are fried in unhealthy oils and coated with salt, making them very high in calories and unhealthy fats," she says.
In addition to all that fat, it's important to note that potato chips also contain little to no nutritional value, which is another major reason they can stand in the way of your weight loss goals. "Potato chips contain little to no fiber, which can help to keep you feeling full and prevent overeating," Wen tells us.
However, there are some healthy chip options out there. By choosing veggie chips and sweet potato chips over your typical chips, you'll be taking one step in the right direction.
5. Processed meats
Processed meats like sausage, bacon, salami, hot dogs, and deli meat are certainly delicious. After all, who doesn't love a tasty hot dog at a cookout? Unfortunately, though, these tasty foods come with a lot of health risks, including a potentially slower metabolism. This is largely due to additives like nitrates, which can lead to insulin resistance and metabolic dysfunction.
"Sausages, bacon, and hot dogs have a high concentration of saturated fats and sodium. They also often contain preservatives like nitrates, disrupting metabolic health and leading to weight gain," Johnson warns. Yikes! Choosing fresh, lean meats whenever possible is always a better option.
The bottom line
Overall, it is especially important to be mindful of what you’re eating if you’re over 40, as metabolism tends to slow down as we age. And while there’s a long list of foods that can support metabolism and an equally long list of ones that can slow it down, sugary cereal, frozen dinners, fast food, and potato chips are all examples of things to avoid. We know cutting these tasty American staples out of your diet can be difficult–and after all, no one is perfect–but keep in mind that making healthy decisions is the best way not only to lose weight, but also to lead a long, happy life.
