Inflammation can be beneficial or harmful, depending on the situation. On the one hand, it is a natural way to protect your body when you hurt or become sick. It can help your body protect itself from diseases and stimulate healing.
On the other hand, chronic inflammation in your body is associated with an increased risk of developing diseases such as diabetes, heart disease and obesity (1, 2, 3).
Interestingly, the food you eat can have a strong effect on inflammation in your body.
Below you will find out what foods cause inflammation in the body.
Foods that cause inflammation in the human body
1. Sugar and high fructose corn syrup
Table sugar (sucrose) and high fructose corn syrup (HFS) are the two main types of added sugar in the diet of modern humans.
Sugar contains 50% glucose and 50% fructose, while high-fructose corn syrup contains about 45% glucose and 55% fructose.
One of the reasons why added sugars are harmful is that they can increase inflammation, which can lead to the development of diseases (4, 5, 6, 7, 8).
In one study, mice that were given a large amount of sucrose developed breast cancer, which spread to their lungs – in part because of the inflammatory response to sugar (6).
In another study, the anti-inflammatory effect of omega-3 fatty acids was attenuated in mice whose diets included large amounts of sugar (7).
Moreover, in a randomized clinical trial in which people drank regular sweetened carbonated drinks, diet carbonated drinks, milk, or water, only those who consumed conventional carbonated drinks had an increased level of uric acid, which causes inflammation and insulin resistance (8 ).
Sugar can also be harmful because it contains excess amount of fructose.
While a small amount of fructose in fruits and vegetables does not cause a negative impact on the body, obtaining a large amount of added sugars is a bad idea.
Consumption of a large amount of fructose is associated with obesity, insulin resistance, diabetes mellitus, liver obesity, cancer and chronic kidney disease (9, 10, 11, 12, 13, 14, 15).
Researchers also note that fructose causes inflammation in the endothelial cells that line the blood vessels, which is a risk factor for cardiovascular disease (16).
It has also been found that high levels of fructose consumption increase some markers of inflammation in mice and humans (10, 17, 18, 13, 19, 20).
Eating foods high in table sugar and high fructose corn syrup causes inflammation that can lead to diseases. It can also neutralize the anti-inflammatory effects of omega-3 fatty acids.
2. Artificial trans fats
Artificial trans fats are probably the most harmful fats among all the fats you consume.
They are produced by adding hydrogen to liquid unsaturated fats to make them more solid fat.
In food ingredient lists, trans fats are often referred to as “hydrogenated” or “partially hydrogenated” oils.
Most margarines and spreads contain trans fats, and they are often added to processed foods to extend shelf life.
In contrast to naturally occurring trans fats contained in dairy products and meat, it has been found that artificial trans fats cause inflammation and increase the risk of developing diseases (21, 22, 23, 24, 25, 26, 27, 28, 29).
In addition to lowering the levels of “good” HDL cholesterol, trans fats can impair the function of the endothelial cells lining your arteries, which is a risk factor for cardiovascular diseases (26).
The use of artificial trans fats is associated with a high level of inflammatory markers, such as C-reactive protein (CRP).
In fact, in one study, CRP levels were 78% higher in women who reported the highest level of trans fat consumption (26).
In a randomized controlled trial involving older women with overweight, hydrogenated soybean oil increased inflammation significantly more than palm and sunflower oils (27).
Studies on healthy men and men with elevated cholesterol levels show a similar increase in inflammatory markers in response to trans fats (28, 29).
Consumption of artificial trans fats can increase inflammation and increase the risk of developing a number of diseases, including heart disease.
3. Vegetable oils
During the 20th century, the consumption of vegetable oils increased by 130%.
Some scientists believe that some vegetable oils, such as sunflower or soybean oil, contribute to inflammation due to the very high levels of omega-6 fatty acids (30).
Although some dietary omega-6 fats are needed, the typical diet of a modern person supplies the body with much more of these fats than people need.
In fact, health experts recommend using more rich omega-3 foods, such as fatty fish, to improve the omega-6 to omega-3 ratio and take advantage of the anti-inflammatory properties of omega-3.
In one study, rats that received an omega-6 and omega-3 ratio of 20: 1 had much higher levels of inflammatory markers than those that received a 1: 1 or 5: 1 ratio (31).
However, evidence that a high intake of omega-6 fatty acids increases inflammation in humans is currently limited.
Controlled studies show that linoleic acid, the most common omega-6 acid in food, does not affect inflammation markers (32, 33).
Before you can draw any solid conclusions, more research is needed.
Some studies show that high levels of omega-6 fatty acids in vegetable oil may contribute to inflammation when consumed in large quantities. Nevertheless, the data are contradictory, and more research is needed.
4. Refined carbohydrates
Carbohydrates have a bad reputation. However, the truth is that not all carbohydrates cause problems.
The ancients for thousands of years consumed raw carbohydrates with a high fiber content in the form of herbs, roots and fruits (34).
However, the use of refined carbohydrates can cause inflammation (34, 35, 36, 37, 38).
In refined carbohydrates, most of their fiber has been removed. Fiber contributes to a feeling of fullness in the stomach, improves blood sugar control and nourishes good bacteria in the intestines.
Researchers suggest that refined carbohydrates in modern diets may stimulate the growth of inflammatory intestinal bacteria, which may increase the risk of obesity and inflammatory bowel disease (34, 36).
Refined carbohydrates have a higher glycemic index (GI) than unrefined ones. High GI foods increase blood sugar more quickly than low GI foods.
In one study, older people who reported the highest levels of high-GI food intake had a 2.9-fold greater risk of dying from an inflammatory disease, such as chronic obstructive pulmonary disease (COPD) (37).
In a controlled study, young healthy men who ate 50 grams of refined carbohydrates in the form of white bread had higher blood sugar levels and an increase in a specific inflammatory marker (38).
High-fiber unrefined carbohydrates are good for health, but refined carbohydrates raise blood sugar levels and contribute to inflammation, which can lead to illness.
5. Excessive alcohol
It has been found that a moderate level of alcohol consumption brings health benefits.
However, a higher amount can lead to serious problems.
In one study, the CRP inflammatory marker increased in people who consume alcohol. The more alcohol they consume, the more their CRP increases (39).
People who drink a lot may develop problems with bacterial toxins from the colon. This condition, often referred to as leaky bowel syndrome, can lead to widespread inflammation that causes damage to organs (40, 41).
To avoid alcohol-related health problems, consumption should be limited to two standard drinks per day for men and one for women.
One drink of alcohol is:
- 355 ml of beer
- 237-266 ml of malt liquor
- 148 ml of wine
- 44 ml distilled alcohol (42)
Excessive alcohol intake can increase inflammation and lead to leaky bowel syndrome, which leads to inflammation throughout the body.
6. Processed meat
Consumption of processed meat is associated with an increased risk of developing cardiovascular diseases, diabetes, stomach cancer and colon cancer (43, 44, 45).
To processed meat include:
- Smoked meat
- Beef jerky
- Semi-finished products (cutlets, dumplings, etc.)
- Fast food
Processed meat contains glycation end products (CNG).
CNGs are formed by cooking meat and some other products at high temperatures. They are known to cause inflammation (46, 47).
Of all the diseases associated with the consumption of processed meat, the strongest is associated with the development of colon cancer.
Although many factors contribute to the development of colon cancer, it is believed that one of the mechanisms is the inflammatory response of colon cells to processed meat (48).
Processed meat contains a large number of inflammatory compounds, such as CNG, and its strong association with the development of colon cancer can be partly caused by an inflammatory reaction.