7 Effects of Greasy Food on Your Body
Greasy foods are not only found at fast food joints but also workplaces, restaurants, schools, and even your home.
Most foods that are fried or cooked with excess oils are considered greasy. They include french fries, potato chips, deep-dish pizzas, onion rings, cheeseburgers, and doughnuts.
These items tend to be high in calories, fat, salt, and refined carbs but low in fiber, vitamins, and minerals.
While they can be an enjoyable treat on special occasions, greasy foods negatively affect your body and health in both the short and long term.
Here are 7 effects of greasy foods on your body.
1. May cause bloating, stomach pain, and diarrhea
Among the macronutrients — carbs, fat, and protein — fat is the most slowly digested (1Trusted Source).
Because greasy foods contain high amounts of fat, they slow stomach emptying. In turn, food spends more time in your stomach, which can cause bloating, nausea, and stomach pain (2Trusted Source).
In people with digestive complaints, such as irritable bowel syndrome (IBS), chronic pancreatitis, or a stomach bug, high levels of fatty foods may trigger stomach pain, cramping, and diarrhea (1Trusted Source).
SUMMARY
Greasy meals delay stomach emptying and may cause bloating, nausea, and stomach pain. In people with certain digestive conditions, these foods may worsen symptoms like cramping and diarrhea.
2. May impair your gut microbiome
Greasy foods are known to harm the healthy bacteria that live in your gut.
This collection of microorganisms, also called the gut microbiome, affects the following:
- Digestion of fiber. Bacteria in your gut break down fiber to produce short-chain fatty acids (SCFAs), which have anti-inflammatory effects and may protect against digestive disorders (3Trusted Source).
- Immune response. The gut microbiome communicates with immune cells to help control your body’s response to infections (4Trusted Source, 5Trusted Source).
- Weight regulation. An imbalance of gut bacteria may contribute to weight gain (6Trusted Source, 7Trusted Source).
- Gut health. Disturbances of the gut microbiome are linked to the development of IBS, while probiotics — live, healthy microorganisms found in certain foods — may help improve symptoms (8Trusted Source, 9Trusted Source, 10Trusted Source).
- Heart health. Healthy gut bacteria may help boost heart-protective HDL cholesterol, while harmful species may produce artery-damaging compounds that contribute to heart disease (11Trusted Source, 12Trusted Source).
A high fat diet, such as one rich in greasy foods, may damage your gut microbiome by increasing the number of unhealthy gut bacteria and decreasing the number of healthy ones (13Trusted Source).
These changes may be associated with obesity and other chronic illnesses, such as cancer, heart disease, diabetes, and Parkinson’s disease (13Trusted Source).
All the same, further research on diet and gut health is needed.
SUMMARY
Unhealthy, greasy foods can disturb the balance of bacteria in your gut, allowing unhealthy strains to grow. This is linked to weight gain and numerous chronic diseases.
3. May lead to weight gain and obesity
Greasy foods, which are cooked in large amounts of fat, may cause weight gain due to their high calorie count.
For example, a small baked potato (3.5 ounces or 100 grams) contains 93 calories and 0.1 grams of fat, while the same amount of french fries packs 312 calories and 15 grams of fat (14Trusted Source, 15Trusted Source).
Observational studies link a high intake of fried and fast foods to increased rates of weight gain and obesity (16Trusted Source, 17Trusted Source, 18Trusted Source).
Obesity is associated with many negative health conditions, including heart disease, diabetes, stroke, and certain cancers (19Trusted Source, 20Trusted Source).
In particular, a high intake of trans fat may cause weight gain.
Trans fats are formed when vegetable oils are chemically altered to stay solid at room temperature. Despite regulations on their use, they’re still found in many greasy foods due to the use of partially hydrogenated vegetable oils in frying and food processing.
Animal studies note that trans fats may lead to small increases in weight — even without excess calorie intake (21Trusted Source, 22Trusted Source).
Additionally, an 8-year study in 41,518 women determined that those with excess weight gained an additional 2.3 pounds (1 kg) for every 1% increase in their trans fat intake (23Trusted Source).
Although other studies haven’t backed up this finding, regularly eating greasy foods is likely to hamper weight control (24Trusted Source).
SUMMARY
Greasy foods are high in calories, excess fats, and trans fats, all of which can lead to weight gain and obesity.
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4. May increase your risk of heart disease and stroke
Greasy foods have several negative effects on heart health.
For example, fried foods have been shown to increase blood pressure, lower HDL (good) cholesterol, and lead to weight gain and obesity, all of which are associated with heart disease (17Trusted Source, 25Trusted Source, 26Trusted Source).
For example, research reveals that potato chips increase inflammation and may contribute to heart disease (27Trusted Source).
Furthermore, your risk of heart disease may be linked to how frequently you eat fried foods (28Trusted Source).
One study found that women who ate 1 or more servings of fried fish per week had a 48% higher risk of heart failure than those who ate just 1–3 servings per month (29Trusted Source).
In another study, people who ate 2 or more servings of fried fish per week had a 63% higher risk of heart attack or stroke than those who ate 1 or fewer servings per month (30Trusted Source).
Additionally, a large observational study in 6,000 people across 22 countries associated eating fried foods, pizza, and salty snacks with a 16% increased risk of stroke (31Trusted Source).
SUMMARY
Greasy foods may increase your risk of heart disease and stroke due to their effects on weight, blood pressure, and cholesterol.
5. May raise your risk of diabetes
Greasy foods may increase your risk of type 2 diabetes (32Trusted Source).
Consuming fast food, which includes not only greasy foods but also sugary drinks, leads to high calorie intake, weight gain, poor blood sugar control, and increased inflammation (33Trusted Source).
In turn, these factors boost your risk of type 2 diabetes and metabolic syndrome — a group of conditions that includes obesity, high blood pressure, and high blood sugar (33Trusted Source).
For example, a large observational study found that eating fried foods 1–3 times per week increased the risk of type 2 diabetes by 15% — but 7 or more instances per week increased the risk by 55% (28Trusted Source).
Another study found that people who ate fast food more than two times per week had twice the chance of developing insulin resistance, which can be a precursor to diabetes, compared with those who ate them less than once per week (34Trusted Source).
SUMMARY
Eating greasy foods raises your risk of type 2 diabetes by increasing body weight and inflammation, as well as impairing your blood sugar control.
6. May cause acne
Many people link greasy foods to breakouts and acne.
In fact, studies associate the Western diet, which is rich in refined carbs, fast food, and greasy items, with acne (35Trusted Source, 36Trusted Source).
A study in over 5,000 Chinese teenagers found that regularly eating fried foods increases the risk of acne by 17%. What’s more, another study in 2,300 Turkish teenagers revealed that eating greasy items like sausages and burgers increased acne risk by 24% (37Trusted Source, 38Trusted Source).
However, the exact mechanism behind this effect remains unclear.
Some researchers propose that poor diet can affect gene expression and alter hormone levels in a way that promotes acne (39Trusted Source, 40Trusted Source, 41Trusted Source, 42Trusted Source, 43Trusted Source).
Western diets with a high ratio of omega-6 to omega-3 fatty acids may likewise cause increased inflammation that leads to acne. While omega-3s occur in oily fish, algae, and nuts, omega-6s are found in vegetable oils, nuts, and seeds.
Oils used in frying greasy foods are high in omega-6s and thus may contribute to an imbalance in this ratio (42Trusted Source, 44Trusted Source, 45Trusted Source).
Some greasy foods like fried doughnuts are also high in refined carbs. These are sugars and refined grains that are stripped of their fiber and many nutrients.
Because sugary foods increase the activity of certain hormones in your body — including androgens and insulin-like growth factor 1 (IGF-1) — they may promote acne by raising your production of skin cells and natural skin oils (40Trusted Source, 46Trusted Source).
Keep in mind that more research on acne’s causes is needed (47Trusted Source).
SUMMARY
Greasy foods may contribute to acne by increasing inflammation and altering gene expression and hormone levels.
7. May impair brain function
A diet rich in greasy, fatty foods may cause problems with brain function.
The weight gain, high blood pressure, and metabolic syndrome linked to greasy foods are also associated with damage to your brain’s structure, tissues, and activity (48Trusted Source, 49Trusted Source, 50Trusted Source).
Two large studies in 5,083 and 18,080 people, respectively, tied diets high in greasy and fried foods to a decline in learning ability and memory, as well as an increase in inflammation (51Trusted Source, 52Trusted Source).
Additionally, diets high in trans fats have been linked to impairments in brain function.
One study in 1,018 adults associated each gram of trans fat eaten per day with worse word recall, indicating memory harm (53Trusted Source).
Furthermore, in a study in 38 women, a higher intake of saturated and trans fats was correlated with poorer word recall and recognition, in addition to poorer performance in spatial tasks (54Trusted Source).
Finally, a review of 12 studies linked trans and saturated fat to dementia risk, although some results were conflicting (55Trusted Source).
Overall, more research is necessary.
SUMMARY
Greasy foods may harm your learning and memory, as well as increase your risk of dementia. Yet, further studies are needed.
