Nutrition Diet: Which fat is best to avoid? A guide to healthy eating

October 12, 2025 •

3 min read

According to the World Health Organization (WHO), industrially produced trans fats contribute to more than 540,000 deaths from cardiovascular disease every year. This stark statistic highlights why it's critical to understand which fat is best to avoid for better long-term health and wellness.

Quick Summary

Industrially produced trans fats are the most detrimental to health and should be eliminated, while saturated fats should be limited. This article details the impact of different fat types on your body and how to make healthier dietary choices.

Key Points

Artificial Trans Fats Are Worst: Industrially produced trans fats, found in many processed and fried foods, offer no health benefits and are the most harmful type of fat due to their impact on cholesterol.
Limit Saturated Fats: While not as dangerous as trans fats, consuming excessive amounts of saturated fat, found in fatty meats and full-fat dairy, can raise 'bad' LDL cholesterol and should be limited.
Prioritize Unsaturated Fats: Monounsaturated and polyunsaturated fats, found in vegetable oils, nuts, and fish, are beneficial for heart health and should be used to replace unhealthy fats.
Read Food Labels Carefully: Always check the ingredients list for 'partially hydrogenated oil' to avoid hidden trans fats, even if the nutrition panel says "0g trans fat".
Choose Whole Foods: Focus on a diet of whole, unprocessed foods and use healthier cooking methods like baking or grilling to control your fat intake.

The Hierarchy of Fats: From Worst to Best

Not all fats are created equal. In the realm of nutrition, some fats are beneficial and essential for body function, while others can have a significant negative impact on your health. Understanding the distinction between these fats is the first step toward building a healthier diet. For decades, trans fats have been identified as the most harmful type of fat to consume due to their dual negative effect on cholesterol levels.

Why Trans Fats Are the Worst Offenders

Trans fats, especially the artificial kind, are produced through a process called partial hydrogenation, which turns liquid vegetable oils into solid fats. This process is used by food manufacturers because it improves a product’s shelf life and flavor stability. However, artificial trans fats are so detrimental to health that many countries and regions, including the U.S. and the WHO, have worked to remove them from the food supply.

Unlike other fats, trans fats simultaneously raise 'bad' LDL cholesterol and lower 'good' HDL cholesterol. This double-whammy effect increases the risk of heart disease, stroke, and type 2 diabetes. Even small amounts of artificial trans fats can harm health, making it the top contender for which fat is best to avoid.

Common Sources of Artificial Trans Fats to Avoid:

Baked goods (cakes, cookies, pies, refrigerated doughs)
Fried foods (doughnuts, fried chicken, french fries)
Shortening and stick margarines
Non-dairy coffee creamers
Packaged snack foods (crackers, microwave popcorn)

Saturated Fats: Consume with Caution

Saturated fats are commonly found in animal products and some plant-based oils and are typically solid at room temperature. A diet high in saturated fat can increase 'bad' LDL cholesterol levels, contributing to heart disease risk. However, recent research suggests the relationship is more nuanced, and its impact can depend on the overall dietary pattern. The key is moderation and replacing saturated fats with healthier alternatives rather than with refined carbohydrates.

Common Sources of Saturated Fats to Limit:

Fatty cuts of meat, bacon, and sausages
Full-fat dairy products like cheese, butter, and cream
Tropical oils, including coconut oil and palm oil
Many commercially prepared baked goods

The Healthiest Fats: Unsaturated Fats

Unsaturated fats—monounsaturated and polyunsaturated—are crucial for a healthy diet and are liquid at room temperature. They can help lower 'bad' cholesterol levels when consumed in place of saturated and trans fats.

Examples of Healthy Fats and Their Sources:

Monounsaturated Fats: Olive oil, canola oil, peanut oil, avocados, nuts (almonds, peanuts, cashews)
Polyunsaturated Fats: Sunflower oil, corn oil, soybean oil, flaxseed, walnuts, and fatty fish (salmon, mackerel, sardines)

Comparison Table: Unhealthy vs. Healthy Fats


Feature	Trans Fat (Artificial)	Saturated Fat	Unsaturated Fat
Chemical Structure	Created by hydrogenation, stable but harmful	Single bonds, 'saturated' with hydrogen	Double bonds, 'unsaturated' with hydrogen
Room Temperature	Solid or semi-solid	Solid	Liquid
Primary Sources	Processed/fried foods, baked goods	Animal products, tropical oils	Vegetable oils, fish, nuts, seeds
LDL ("Bad") Cholesterol	Raises it significantly	Raises it	Lowers it
HDL ("Good") Cholesterol	Lowers it	Has varied effects	Can raise it
Health Impact	Extremely detrimental, no health benefits	Detrimental when in excess, moderation is key	Highly beneficial for heart health

How to Make Smart Choices for Your Nutrition Diet

Reading nutrition labels is one of the most effective ways to avoid harmful fats. Even if a product claims to have "0g trans fat," regulations allow it to contain small amounts per serving. To be sure, always check the ingredients list for "partially hydrogenated oil" and avoid the product if you see it.

Furthermore, focusing on whole, unprocessed foods is the best strategy. By preparing your meals from scratch, you have complete control over the types of fat you consume. Simple cooking methods like baking, steaming, and grilling are healthier than deep-frying.

Conclusion

In summary, the answer to which fat is best to avoid? is unequivocally artificial trans fats. These fats offer no health benefits and pose significant risks, especially for heart health. While saturated fats should also be consumed in moderation, they are not as damaging as trans fats and can be part of a balanced diet when replaced with healthier unsaturated fats. By prioritizing whole foods, reading labels carefully, and opting for unsaturated fats, you can build a nutritional diet that protects your heart and overall well-being. For more in-depth guidance on fats and cholesterol, the American Heart Association offers valuable resources on their website.

Frequently Asked Questions

Saturated fat is typically solid at room temperature and found in animal products and tropical oils. Trans fat, especially the artificial kind, is created by adding hydrogen to liquid oils to make them solid and extend shelf life. Trans fat is more harmful than saturated fat, as it both raises bad cholesterol and lowers good cholesterol.

Artificial trans fat is considered the most dangerous type of fat for your health. It offers no health benefits and is linked to increased risk of heart disease, stroke, and type 2 diabetes by negatively impacting cholesterol levels.

Trans fats are commonly found in processed and fried foods, including baked goods like cakes, cookies, and pie crusts, fried items like french fries and doughnuts, stick margarine, and some snack crackers.

To avoid artificial trans fats, read the ingredients list carefully. Look for phrases like "partially hydrogenated oil". Even if a label says "0g trans fat," it can still contain small, measurable amounts if this ingredient is listed.

Not all saturated fats are created equal, and their impact can vary based on your overall diet. While limiting saturated fat is recommended, some newer studies suggest that the overall dietary pattern and what you replace saturated fat with (healthy fats instead of refined carbs) is more important.

Healthy fats, known as unsaturated fats, include monounsaturated and polyunsaturated types. Good sources are olive oil, avocados, nuts, seeds, and fatty fish like salmon and mackerel.

Yes, coconut oil is very high in saturated fat. While often marketed as a healthy option, it contains even more saturated fat than butter and should be used sparingly.