Like proteins and carbs, fats are vital nutrients that promote metabolism, health, and well-being. However, the type of fats we eat profoundly impacts our heart and overall health. The World Health Organization (WHO) and its Member States and those of the Pan American Health Organization (PAHO) aim to eliminate industrially produced trans fats from the food supply by the end of 2025. Many countries already have. Why the commotion?
In addition to proteins, carbohydrates, vitamins, and minerals, fats are essential nutrients for the body.
Fats come in various forms, some of which are healthier than others. Polyunsaturated and monounsaturated fats are preferred over saturated fats and trans fats.
Extensive studies demonstrate the negative health effects of consuming chemically engineered trans fats (not those found naturally in animal products), including an increased risk of coronary heart disease, cancer, and diabetes.
Studies suggest that saturated fats pose higher risks than unsaturated fats to overall health, and the majority of dietary fat intake should come from unsaturated fats.
Naturally occurring trans fats are found in meat and dairy, but chemically engineered trans fatty acids used in many foodstuffs are the concern. Scientific research shows that trans fat consumption increases the risk of heart disease, diabetes, and cancer. But what about saturated vs. unsaturated fats? Is there sufficient evidence that health risks also abound with saturated fat consumption? Are more regulations needed, or do we let individuals decide?
The trans fat ban: is it enough?
According to the PAHO, ingesting trans fats as >1% of one’s total energy intake increases the risk of heart attacks and death. Trans fat consumption accounts for over 500,000 coronary heart disease deaths globally. Reducing the use of trans fats in a nation’s food supply through regulations, such as limiting the amount to 2% or less of the total fat content or banning partially hydrogenated oils, lessens the risk. The U.S. achieved this benchmark between 2018 and 2020.
So if the U.S. has already banned trans fats, is that all that needs to be done? No. We learn more about the foods and ingredients we eat daily, and saturated fats are emerging as the new trans fat concern. While not nearly as unhealthy as trans fats, consumption above daily recommendations may increase the risk of negative health outcomes. Understanding fats, your body’s needs, and how to eat healthily and responsibly goes a long way to ensuring a healthy life.
However, food shortages and insecurities often expose people to high levels of calorically dense and highly fatty foods (especially saturated fats), increasing the risk of adverse health events. So, through research and dietary oversight, healthy messages need to be relayed to the public that helps guide healthy food choices. Rather than focus on banning ingredients, we need to focus on sustainable food choices and healthy options for all.
Types of fats in food
So what is the scoop on fats? Good or bad? Fats support your cells, protect your organs, help in body temperature regulation, and help the body produce energy. We need fats to make key hormones in the body, and the presence of fats helps nutrient absorption.
For the scientifically curious, saturated fatty acids are "saturated" with hydrogen without having any double bonds. Fats that are solids at room temperature are saturated. These are naturally found in animal products, and some studies show that they can contribute to increased cholesterol levels, thereby elevating one’s chance of stroke and heart disease. Examples include butter, cheese, beef, lamb, the skin on poultry, lard, ice cream, palm and palm kernel oils, and some fried or baked foods. Dietitians recommend limiting our saturated fat daily intake to only 5–6% of total calories.
However, the available evidence about the negative health effects of saturated fats is not quite as clear-cut as for trans fats. In a 2021 review, researchers questioned “Dietary Saturated Fats and Health: Are the U.S. Guidelines Evidence-Based?” and concluded that insufficient evidence exists to make blanket bans. Further, they suggest that more research is needed, considering that while some products, like dairy, may have saturated fats, their overall nutrient profile plays a role in how the fats are absorbed and metabolized. This nutrient interaction may help to negate some of the ill effects of saturated fats.
Thus, while a ban on trans fats was scientifically justified and has decreased heart attacks in countries where they have been banned, a similar ban on saturated fats cannot be suggested until more research is obtained and evaluated.
Unsaturated fats, or fats that are liquid at room temperature, are either monounsaturated or polyunsaturated, both of which our bodies require.
Most of us have heard recommendations for omega fatty acids, generally divided into omega-3 and omega-6s. They have varying effects on promoting heart health and lessening inflammation, and they are essential to the body. These omegas represent polyunsaturated fats. Daily consumption of polyunsaturated fats should be ≤10% of total daily calories.
- Omega-3 fatty acids. Omega-3 fatty acids are naturally found in fish such as sardines, herring, trout, salmon, or tuna. They also are found in chia seeds, flaxseeds (and oil), and walnuts.
- Omega-6 fatty acids. Omega-6 fatty acids naturally occur in several oils (safflower, corn, soybean, and sunflower) and in sunflower and pumpkin seeds.
While saturated fats are derived from animal products, monounsaturated fats are plant-based. When consumed instead of trans fats or saturated fats, they can help lower one’s risk of heart disease.
Monounsaturated fats include:
- Peanut butter
- Various plant oils
- Many seeds and nuts
Dietitians suggest that approximately 20% of total daily calories should be from monounsaturated fats.
Trans fats (trans fatty acids)
Small levels of naturally occurring trans fatty acids can persist in food items because these fats are produced in animals’ GI tracts. Trans fats from natural animal products usually only make up 4% or less of the total fat content (e.g., butter, cream, beef). However, we create synthetic trans fats by adding hydrogen to different vegetable oils (liquids) to make them more solid.
When we hydrogenate, adding hydrogen to either mono- or polyunsaturated fatty acids, they can be converted into saturated fats or trans fats. Chemically engineered trans fats, first developed in 1901, originate from partially hydrogenated unsaturated fats. Margarine and Crisco, for example, became vegetable oil spreads with longer shelf lives than butter. Further, the hydrogenation increased the fat’s melting point, making it better adapted for frying. These fats were developed and used because they provided cost savings and helped extend the product's shelf life.
As early as the 1950s, research demonstrated elevated blood lipid levels (cholesterol) when trans fats were consumed, though, at that time, the negative ramifications were just being evaluated. By the 1990s, clear evidence of harm appeared in study after study, including increased inflammation and damage to the blood vessel lining (endothelium). By the early 2000s, labeling regulations required transparency regarding the amount of trans fats in U.S. products. And finally, in 2018, the FDA banned partially hydrogenated oil use completely.
However, while the FDA banned manufacturers from adding trans fats to foods in 2018, they extended compliance until 2020 for foods already on the shelves. When traveling outside the U.S. to countries where trans fats are still permitted, read labels carefully. Hidden trans fats could be found in hydrogenated oils, potato chips, some types of popcorn, frozen pizza crusts, non-dairy creamers, non-dairy spreads/margarine, and even cookie dough. Thankfully, the U.S. is basically trans-fat-free!
The type of fat matters
Eating foods with healthy fats helps define a healthy diet. Not all fats are bad; in addition to proteins and carbohydrates, our bodies require fats to survive. The key is not eating fats in excess of what the body needs and eating healthy fats that support healthy metabolism and do not negatively affect our heart health or overall vitality.
You need to recognize what fats are, where they come from, and what forms they come in, and balance out how many calories you intake with the activity and energy you expend. Choosing unsaturated over saturated fats and lean meat/poultry or low-fat dairy products will be safer in the long run.
Trans fats banned. Are saturated fats next?
Luckily, the U.S. has regulated non-natural trans fats, lessening Americans’ chances of developing coronary heart disease and risks of cancer and diabetes. Hopefully, the global community will follow the WHO’s recommendation, and industrial trans fats will be removed from all foodstuffs worldwide. Many tout this ban as a key public health achievement, and hopefully, it will become a global ban in short order.
But what about saturated fats? Do they pose health risks similar to trans fats? The evidence is inconclusive, and current recommendations to keep saturated fat intake to 10% or less of your total caloric intake still stand as the current recommendation. Should more regulation occur on what goes into our foods? Or should individuals control how much sugar and fat they consume? Whether regulation on saturated fatty acids is warranted is one of the recent questions for public health professionals and researchers worldwide. Only time will tell.
- Pan American Health Organization (PAHO). Trans-fatty Acids.
- The Milbank Quarterly. The Demise of Artificial Trans Fat: A History of a Public Health Achievement.
- Nutrients. Dietary Saturated Fats and Health: Are the U.S. Guidelines Evidence-Based?
- World Health Organization (WHO). More than 3 billion people protected from harmful trans fat in their food.