In 1992, a bright green box hit supermarket shelves...
And it became the iconic symbol of a nationwide nutritional craze.
The box's contents?
That'd be SnackWell's Devil's Food Cookie Cakes. They had chocolate, tasted sweet, and, most important, were 100% fat-free.
They became massively popular, even briefly beating out Oreo cookies as the No. 1 cookie in America.
And it just so happens that these glossy, chocolatey rounds had a psychological phenomenon – no, a psychological trap – named after them: the SnackWell's Effect.
The logic back then was that fat was the main enemy of our waistlines and health. After all, it has the most calories compared with carbohydrates and protein. So the thinking was that if you didn't have the fat, then that means the "guilt" was gone, too... opening the floodgates of overindulgence.
Making things worse was the fact that lots of these low-fat foods were packed with sugar to make up for the missing flavor. And without the fat to trigger the release of the "OK, I'm full" hormones, it was the perfect recipe for insatiable hunger and insulin spikes. You didn't eat just one or two cookies – you ate the whole tray.
That era forever haunts me. Those were times when folks thought we needed to stop eating all fats... including the ones we need to keep our bodies functioning properly. They shunned natural, healthy fats and ended up gorging on refined sugars instead.
And now we're paying the price...
The sugar-for-fat tradeoff resulted in a surge in metabolic syndrome. This isn't just one disease – it's a cluster of dangerous health conditions like high blood pressure, low "good" cholesterol, high triglycerides, excess belly fat, and, of course, high blood sugar. Staying on this path puts you at high risk of heart attack, stroke, and diabetes.
What's more, a study published last month in Nature Communications found that the global prevalence of metabolic syndrome more than doubled between 2000 and 2023. Worldwide, 1.54 billion people are trapped in a cycle of metabolic dysfunction.
Today, we're going to dive into the truth behind the good, the bad, and the inflammatory...
What are the different kinds of fats?
There are three main types of fats:
- Unsaturated fats: They include monounsaturated fats ("MUFAs") and polyunsaturated fats ("PUFAs"). Unsaturated fats can be found in plenty of natural foods like olive oil, fish, and nuts.
- Saturated fats: These occur naturally in foods like meat, butter, and coconut oil. They're also solid at room temperature.
- Trans fats: These are the biggest villains. They're purely man-made and are difficult for your body to break down. In fact, they send your immune system into overdrive, promoting inflammation and wreaking havoc on your body.
Why are they different? Is it their structure?
We don't want to get too far into the organic chemistry behind fat molecules. But basically, fats differ based on the arrangement of their atoms.
All fats consist of chains of carbon atoms with attached hydrogen atoms. Now, unsaturated fats have double bonds between some of their carbons, meaning they look like this (the double line is the double bond)...
That space in the middle allows enzymes to get in and break down the fat more easily. Monounsaturated fats have a single double bond, whereas polyunsaturated fats have more than one – the more bonds, the easier they are to process.
Saturated fats don't have any double bonds. They're "saturated" with hydrogen atoms, so there's no room for enzymes to easily break them down. (If you remember high school chemistry, you'll know that a carbon atom can only bond in four spots). Take a look...
The dangerous fat in the family is the artificially produced trans fat. These fats have a double bond, but the hydrogens swap sides. "Trans" in Latin means "across." That makes it extremely hard for our bodies to break them apart.
Which ones are good for you?
I've written many times about the benefits of MUFAs. These are the best kinds of fat.
MUFAs, such as those in olive oil, lower your levels of low-density lipoprotein (the so-called "bad" cholesterol). Some studies show that MUFAs also help keep insulin levels in check.
We need PUFAs for our bodies to function properly, but we can't make them on our own. We have to get them through our food. These include the omega fatty acids.
Omega-3 fats (from fish as well as other sources) reduce inflammation. Inflammation increases your risk of heart disease and diabetes, and it accelerates aging. So there are significant health benefits to eating fish.
Omega-6 fats also help promote brain health and, along with omega-3s, help keep your bones healthy and your metabolism on track.
Now, there's a bit of a controversy over how much of each one you need. Omega-3s are great for your health and are a fatty acid I've advocated for in my write-ups on fish.
However, too many omega-6 fatty acids can trigger inflammation – they're almost the opposite of omega-3s. People ideally should be eating omega-6s and omega-3s in a ratio no greater than 4:1.
The problem is that omega-6s are also in heavily processed vegetable oils. The American obsession with these oils means we're getting about 16 omega-6s for every 1 omega-3.
Overall, natural sources of unsaturated fats are essential for a long, healthy life.
What We're Reading...
- Something different: What "weird-looking otter poop" could mean.
Here's to our health, wealth, and a great retirement,
Dr. David Eifrig and the Health & Wealth Bulletin Research Team
January 22, 2026