It’s 2019, and it’s time we’ve stopped fearing dietary fat. Many experts bemoan the name. The fat you eat doesn’t make you fat inherently. Anything eaten in excessdoes. Of course, it maycause weight gain, but don’t blame the fat, blame the habit. Fat is incredibly important for our health, from helping us to absorb fat-soluble vitamins like Vitamin A, E, and D to managing inflammation. [1] Nevertheless, not all fats are created equal, and there does exist a particular type of fat that ought to be avoided. Or rather, kept to a bare minimum. Let’s broaden the discussion of dietary fat and highlight the one kind of fat that’s bad to the bone. Are you ready? Then let’s get to it!

Meet Trans Fats

Trans fats, or trans fatty acids, are a special class of fats. Much like we have monounsaturated fats and polyunsaturated fats, trans fats have their own effects on our health and longevity. However, unlike the former two, trans fats can be found both naturally and artificially. The majority of trans fats we come across are created through the hydrogenation of oils, a chemical process that helps to increase shelf life and stability. [2] However, they do occur naturally- albeit in trace amounts- in animal products, from meat to dairy. At the time being, the bulk of the research on the harmful effects of trans fats focuses on the processed, industrial kind, and not that found in nature. [3]

Why They’re Bad

The reason that trans fats are a doctor’s worst nightmare is because of effects on cholesterol. They’ve been shown to raise harmful LDL cholesterol while lowering good HDL cholesterol, which increases your risk for atherosclerosis, heart disease, and stroke. [4] On top of that, trans fats are known to be highly inflammatory to the body, once again paving the way for pro-inflammatory diseases and conditions such as diabetes, dyslipidemia, and coronary artery disease, amongst many others [5] [6]
When it comes to trans fats, the phrase “everything in moderation” is ill-advised. You cannot (and should not) “moderate” something that’s incredibly harmful to your body. And the Food and Drug Administration (FDA) agrees. It no longer recognizes processed oils (which are loaded with trans fats) as GRAS (generally recognized as safe) and has even taken steps to ban it on nationwide level. [7] Research as recent as 2017 even shows that people living in areas where trans fats were banned had fewer hospitalizations for either heart attack or stroke in comparison to those living in un-banned trans fat areas. [8]
However, if heart health and disproval by the FDA is not enough compelling evidence to make you ditch these guys for good, then here’s some more research for you to consider.

As you know, my pet health topic is about the gut (aka, the forgotten system). A one-of-a-kind mouse study from 2018 aimed to see just what trans fats did to the beneficial bacteria that live in the gut and came to a startling conclusion. The mice that had been given trans fatty acid rich oil had increased levels of harmful bacteria (for the nerds: Proteobacteria and Desulfovibrionaceae) and reduced levels of beneficial bacteria (Bacteroidetes and Lachnospiraceae). On top of that, the trans fats managed to (unsurprisingly) increaseinflammation while loweringthe beneficial byproducts (post-biotics) of the good bacteria (butyric acid and valeric acid– both of which help to lower inflammation and support gut health). [9] While this is an animal-based study, it does open the door to further research on trans-fat and its effects on the human microbiome. One thing is for sure- don’t ever feed trans-fat to your pets!

But let’s not let trans-fat off the hook just yet. If you want human studies, then I’ve got them right here. In a pretty big study examining over 80,000 women, it was shown that the subjects with a high intake of trans-fat had up to a 40% higher risk of developing diabetes. [10] The famous Nurses’ Health Study shows that in pre-menopausal women with a high intake of trans-fat, the risk of breast cancer development was further increased. [11]

There’s also research to show that trans fats can damage the endothelium or inner lining of blood vessels, thereby increasing the risk of endothelial cancer. In a 2001 study published in Arteriosclerosis, Thrombosis, and Vascular Biology (a medical journal tied to the American Heart Association), replacing saturated fats with trans-fats had frighteningly impaired the ability for arteries to dilate by as much as 29%. [12] Similar findings were published in 2004 in the American Journal of Clinical Nutrition, showing that replacing carbs and monounsaturated fats in HEALTHY male subjects had increased markers for endothelial dysfunction. [13]

As you can see, trans fats are nothing to sneeze at. If even the FDA is against it, then you know it’s something to take seriously.

Where to Find Them

Trans fats are industrial food. Or rather, food-like imposters. They hide in plain sight in processed foods, including:

• Baked Goods (cookies, cakes, cake frosting, pies, doughnuts)
• Pie Crusts
• Refrigerated Dough
• Frozen Biscuits
• Breakfast Sandwiches
• Sweet Pies (meat pies)
• Microwaveable Popcorn
• Crackers
• Candy (particularly the creamy kind)
• Frozen Pizza
• Margarine (aka, FAKE butter)
• Vegetable Shortening
• Coffee Creamer (dairy and non-dairy)
• Potato and Corn Chips
• Fast Food (especially fried fast food, from chicken to French fries)
• Partially Hydrogenated Oils (in the form of canola, soybean, and vegetable oil- look for them in salad dressings, marinades, sauces, and condiments)

[14] [15] [16]

Also, buyer beware. Despite the FDA ban on trans-fats, manufacturers in the US can still label their products as “free of trans fats” so long as the amount of trans fats is less than 0.5 grams. [17] While it’s important to read the ingredients list on a food label, the easiest way to avoid trans fats altogether is focusing on a whole foods diet, which is devoid of the processed, toxic junk found in industrial foods. And as for the aforementioned naturally occurring traces of trans fats from animal foods, don’t worry just yet. Like I said before, the research on these fats isn’t hasn’t found any evidence to warrant a ban on animal products. [18]

I still stand by my stance on fat: we need to stop treating it like it’s public enemy #1! It is not the enemy here. All of the negative downsides we associate with it really should be pointed in the direction of the processed variety in the form of trans fats. Otherwise, the kind that we can obtain naturally from things like nuts and seeds, avocado, fish, eggs, olives, and coconut is not only safe but extremely healthy. So, have no fear! Stick with nature, and avoid the franken-foods!

Sources:

[1] https://medlineplus.gov/ency/patientinstructions/000104.htm
[2] https://www.medicinenet.com/script/main/art.asp?articlekey=11091
[3] https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/trans-fat
[4] https://www.webmd.com/heart-disease/features/high-cholesterol-dangers#1
[5] https://www.ncbi.nlm.nih.gov/pubmed/16713393
[6] https://www.health.harvard.edu/newsletter_article/Inflammation_A_unifying_theory_of_disease
[7] https://www.webmd.com/diet/guide/understanding-trans-fats
[8] http://jamanetwork.com/journals/jamacardiology/article-abstract/2618359?resultClick=1
[9] https://www.ncbi.nlm.nih.gov/pubmed/30120538
[10] https://www.nejm.org/doi/full/10.1056/NEJMoa010492
[11] https://www.ncbi.nlm.nih.gov/pubmed/16843178
[12] https://www.ncbi.nlm.nih.gov/pubmed/11451757
[13] https://www.ncbi.nlm.nih.gov/pubmed/15159225
[14] https://health.clevelandclinic.org/avoid-these-10-foods-full-of-trans-fats/
[15] https://www.webmd.com/food-recipes/trans-fats
[16] https://www.healthline.com/nutrition/trans-fat-foods#section7
[17] https://www.ncbi.nlm.nih.gov/pubmed/20338284
[18] https://www.nature.com/articles/ejcn201134