Trying to lose weight is difficult enough without having to deal with foods that cause weight gain with more than excess calories. Find out which toxic foods can actually prevent your metabolism from burning more fat.

Once you know the most toxic foods that impede weight loss, you’ll be able to avoid any excess, and you should at least consider dropping them from your eating habits altogether. From known questionable ingredients to less known problem foods, here’s what to stay away from when you’re trying to lose weight.

Sweets with High Fructose Corn Syrup

A real problem in most Americans’ diets, high fructose corn syrup is currently the no. 1 source of calories, according to a study conducted at Tufts University. 

HFCS is more than just a fattening food ingredients, it also increases levels of hormones involved in the fat storing process, and it can also increase your appetite. Say goodbye to cheap sweet treats and avoid it completely.


Partially hydrogenated oil is always bad, but in shortening it’s even worse, delivering an unhealthy dose of trans fats. It doesn’t just increase your risk of obesity, it can also clog your arteries and even put you at risk of developing metabolic syndrome. Since partially hydrogenated oils are among the most toxic foods that impede weight loss, you’re better off just saying no.

Corn Fed Beef

Corn Fed Beef

If you’re not buying grass-fed beef, you should improve your diet and weight loss efforts by not eating it at all. Corn fed beef has a lower nutritional value, and it also has a higher content of two harmful ingredients: saturated fat and omega-6 fatty acids. While saturated fats can obviously affect your weight loss progress, omega-6s have an inflammatory effect on the body, throwing another wrench in your metabolism.

See also: 10 Healthier Alternatives to Cow's Milk

Foods with Butylated Hydroxyanisole (BHA)

One of the most toxic foods that impede weight loss, BHA is a common preservative, which has been linked to an increased risk of cancer. Even if you’re not worried about that, this chemical can affect endocrine processes in the body, affecting both hormones that aid fat storage and those that prevent it.

Non-Organic Potatoes

If you’re not buying organic potatoes, you’re eating more than just herbicides and pesticides. Regular potatoes are also treated against sprouting. Absorbing more toxins that most other root vegetables, they’re also exposed to fungicides. Buy organic. It may be a bit more expensive, but all the chemicals won’t interfere with your diet.


Diet sodas can be just as harmful to your weight loss efforts than regular ones. Even if you’re not drinking huge amounts of sugar in regular soda, the artificial food colors and preservatives in the diet versions have also been associated with obesity. If you’re worried about the most toxic foods that impede weight loss, then stop drinking soda completely.

Canned Tomatoes

Tomato skins are rich in lycopene, an antioxidant which can help you lose weight, but if you’re only eating canned tomatoes, you’re at risk for a hormone imbalance that will prove to be an obstacle when losing weight. Bisphenol-A, a synthetic estrogen found in the lining of tin cans, has been linked to obesity and diabetes. If you can’t buy fresh, choose tomatoes in glass bottles or tetra paks.

Pesticides Impede Weight Loss

Non-Organic Apples

The fruit equivalent of potatoes, apples can be one of the most toxic foods that impede weight loss, since they absorb so many pesticides. Switch to organic apples now.

More: 10 Weird Reasons to Weight Gain

Non-Organic Yogurt

While Greek yogurt is a great addition to your diet, non-organic yogurt is definitely one of the most toxic foods that impede weight loss. The reason is that it’s made from the milk of cows treated with growth hormones. Their byproduct is a hormone called insulin-like growth factor (IGF-1), which can not only get you to gain weight, it also increases your risk of developing cancer.


If you love flatbreads, stay away from those that include brominated flour (or potassium bromate) in the list of ingredients. Linked to gastrointestinal troubles, potassium bromate has also been associate with disorders that affect the nervous system and your kidneys.