What are the side effects of grease?

January 13, 2026 •

3 min read

Globally, millions are spent every year clearing sewer blockages caused primarily by the improper disposal of fats, oils, and grease (FOG). This highlights just one of the serious side effects of grease, which can impact not only public infrastructure but also personal health and the wider environment.

Quick Summary

Grease exposure and consumption carry significant health and environmental risks, including digestive upset, heart disease, weight gain, skin problems, plumbing clogs, and environmental pollution.

Key Points

Health Complications: High consumption of dietary grease from fried foods can lead to heart disease, obesity, digestive problems like bloating and diarrhea, and skin issues such as acne.
Occupational Hazards: Workers with prolonged exposure to industrial mineral greases risk skin conditions like dermatitis and certain cancers, especially from used engine oil containing polycyclic aromatic hydrocarbons (PAHs).
Respiratory Damage: Inhaling oil mist from heated industrial greases can cause respiratory irritation and lead to systemic organ damage over time.
Plumbing Disasters: Improperly poured grease cools and solidifies in pipes, causing significant blockages known as "fatbergs," which can lead to sewage backups and costly infrastructure damage.
Environmental Pollution: Disposed grease pollutes waterways, harms aquatic life by reducing oxygen levels, and contaminates soil by disrupting aeration.
Prevention is Key: Mitigating grease's negative effects requires both dietary changes, like choosing healthier cooking methods, and proper waste disposal practices for both food and industrial greases.

Health Risks of Consuming Grease

Consuming excessive amounts of dietary grease, often from fried and processed foods, can lead to various negative health outcomes. While occasional consumption may not be harmful, a diet consistently high in fat contributes to chronic conditions, particularly due to unhealthy saturated and trans fats found in many fried foods.

Digestive System Issues

Grease consumption can immediately affect the digestive system. High-fat foods digest slowly, causing discomfort. Individuals with conditions like IBS may experience more severe reactions.

Bloating and nausea: Slow digestion can cause feelings of fullness, bloating, and nausea.
Diarrhea: Too much grease can accelerate the passage of stool through the intestines.
Impaired gut microbiome: A high-fat, low-fiber diet can reduce beneficial gut bacteria diversity and potentially cause inflammation.

Cardiovascular Health Concerns

A major long-term risk of a high-grease diet is its impact on the heart. Saturated and trans fats, common in greasy foods, increase LDL ("bad") cholesterol.

Arterial plaque buildup: High LDL cholesterol leads to plaque in arteries (atherosclerosis).
Increased heart attack and stroke risk: Plaque restricts blood flow, raising the risk of heart attack or stroke.
Chronic inflammation: Compounds from repeatedly heated oils cause oxidative stress and inflammation, increasing heart disease risk.

Weight Gain and Obesity

Greasy foods are high in calories. This dense caloric content contributes to a surplus when consumption exceeds expenditure, leading to fat storage and weight gain. Obesity is a risk factor for conditions like type 2 diabetes and certain cancers.

Skin Problems and Acne

There is evidence linking high-fat diets to skin issues like acne.

Increased sebum production: Dietary fats can boost sebum, the skin's oil.
Clogged pores: Excess sebum, combined with skin cells and dirt, can clog pores, facilitating acne-causing bacteria.
Inflammation: High saturated fat intake might promote inflammation, potentially worsening skin conditions.

Occupational and Environmental Exposure Side Effects

Industrial greases also pose health and environmental threats.

Occupational Hazards

Workers in contact with industrial lubricants face risks.

Skin contact: Exposure to mineral oils and greases can cause dermatitis. Used engine oil contains PAHs, linked to skin and testicular cancer.
Inhalation risks: Breathing oil mist or fumes can cause respiratory issues and introduce toxins affecting organs.
Injuries: Grease spills create slip hazards.

Environmental Pollution

Grease released into the environment is a pollutant.

Water contamination: Grease entering waterways forms a surface layer, blocking sunlight, reducing oxygen, and harming aquatic life.
Soil contamination: Spills contaminate soil, reducing aeration and harming microorganisms.
Air pollution: Grease production and disposal can release pollutants.

Plumbing and Infrastructure Damage

Improper disposal of fats, oils, and grease (FOG) is a costly cause of plumbing and sewer damage.

Grease solidifies as it cools, sticking to pipes.
This layer traps debris, forming blockages over time.
Large obstructions, known as "fatbergs," cause sewage backups and require expensive repairs.
Fatbergs damage municipal sewers, leading to significant maintenance costs.

Healthy Alternatives and Prevention

Preventing the negative effects of grease involves conscious choices.

Dietary choices: Limit fried foods. Choose baking, grilling, steaming, or air frying to reduce grease.
Use healthier oils: Opt for unsaturated oils like olive or canola over saturated ones like butter.
Proper grease disposal: Never pour cooking grease down drains. Let it cool, solidify, and dispose of it in the trash.
Use dry cleanup: Wipe greasy pans with paper towels before washing.
Personal protection: Workers should use PPE and follow safety protocols for industrial greases. CDC provides resources on chemical exposure safety.
Environmental stewardship: Dispose of industrial greases properly, using recycling where available.

Grease Side Effects: Dietary vs. Industrial


Feature	Edible Grease (Dietary)	Industrial Grease (Occupational/Environmental)
Primary Source	Fried foods, fatty meats, processed snacks	Engine oil, machinery lubricants
Major Health Risks	Heart disease, obesity, digestive issues, acne	Skin irritation/cancer, respiratory problems, burns, systemic organ damage
Immediate Symptoms	Bloating, nausea, indigestion, diarrhea	Skin rashes, eye/throat irritation
Long-Term Conditions	Type 2 diabetes, heart disease, non-alcoholic fatty liver disease (NAFLD)	Dermatitis, skin cancer, testicular cancer
Environmental Impact	Municipal sewer blockages (fatbergs), water contamination via wastewater	Soil/water contamination, harmful air emissions
Key Prevention	Limit consumption, use healthy cooking methods, proper kitchen disposal	Use PPE, follow safety protocols, proper waste management

Conclusion

Grease has significant negative side effects on health, the environment, and plumbing. Excessive dietary grease increases the risk of chronic conditions like heart disease and obesity. Industrial greases pose severe occupational health risks, including cancer. Improper grease disposal causes plumbing blockages and environmental pollution. Understanding these risks and adopting preventive measures in diet, waste disposal, and workplace safety can mitigate the adverse impacts of grease.

Frequently Asked Questions

Yes, research indicates that excessive dietary fat can increase sebum production, the skin's natural oil. This excess sebum can clog pores and promote inflammation, contributing to acne breakouts.

A fatberg is a large, solid mass of congealed fat, oil, and grease (FOG) that has accumulated and solidified in a sewer system, where it mixes with other debris like flushed wipes to form a massive blockage.

When grease goes down the drain, it cools and solidifies, clinging to the inside of your pipes. This buildup traps other debris, leading to clogs that can cause backups and require expensive professional cleaning.

Grease pollution, particularly from sewer overflows, contaminates rivers and lakes. It forms a film on the water's surface, which depletes oxygen and is toxic to aquatic ecosystems. It also contaminates soil upon improper disposal.

Allow the grease to cool and solidify. Scrape it into a disposable container with a tight lid, such as a can or old jar, and throw it in the trash. Never pour it down the sink or toilet.

Inhaling oil mist can cause irritation to the nose, throat, and lungs. Long-term exposure can lead to more serious health problems, as the body can absorb toxic compounds that affect organs like the liver and kidneys.

While oily skin can initially show fewer fine lines due to natural moisture, a long-term buildup of excess oil can break down collagen, leading to a loss of elasticity and potentially contributing to sagging and premature aging if not properly managed.