“Refined sugar” is a phrase that strikes fear in our hearts. As consumers, we’re all too familiar with America’s war on sugar. Deemed a “silent killer,” sugar is identified as a major cause of obesity, heart disease, and diabetes. The past decade has seen a cascade of sugar substitutes, including Splenda and a slew of other trendy packets that cheerfully promise “sugar free.” Is this really the entire story, though? For diabetics, and for those of us who want to maintain our health, there is yet another line on the nutrition label that is far too often overlooked.
Most people in America are aware of the dangers of type II diabetes. After all, almost one in every ten people in the country is diabetic. One in every five health care dollars is spent caring for people with diabetes. There’s no question about it — this disease is a national problem.
Type II diabetes is characterized by the body’s impaired ability to respond to insulin and subsequently metabolize sugar, or glucose. Ideally, whenever we eat, our bodies break food down into glucose, which is absorbed into the blood and taken up by muscle cells to be stored or burned for energy. There’s a catch, though. Glucose in the blood needs a key to get into our cells, and that key is insulin. Cells in the pancreas, called beta cells, are responsible for the secretion of insulin that regulates our blood sugar levels.
When blood sugar levels are always elevated from eating refined sugar, over time, the body stops responding to insulin — a condition called insulin resistance. Insulin resistance is the start of a vicious cycle that leads to chronically elevated blood sugar levels. Because no sugar can enter cells, they are starved of energy, leading to damage to the eyes, kidneys, brain, and heart.
It is a commonly held assumption that refined sugar alone causes elevated blood sugar levels. However, what if this is only half the story? What if our bodies make enough insulin, but the key doesn’t work? There’s gum that is blocking the lock. That gum is fat. Not just any fat — saturated fat.
Scientists have studied the role of fat and blood sugar for nearly a century. In a 1927 study, young healthy people were separated into two groups. One group was fed a fat-rich diet including olive oil, butter, and mayonnaise, while the other group was fed a carbohydrate-rich diet of potatoes, bananas, rice, oatmeal, and bread. Because carbs are directly converted into glucose, one might expect the carbohydrate-rich diet would cause higher blood sugar. However, the study found that the glucose intolerance of the fat-rich diet group spiked compared to that of the sugar group. In fact, participants in the former had double the blood sugar levels. It took scientists nearly seven decades to unravel this mystery.
How exactly can saturated fat cause insulin resistance? A chronic increase in saturated fat levels in the blood is toxic to pancreatic beta cells. Fat breakdown creates a slew of toxic breakdown products including free radicals, causing mitochondrial dysfunction, increase in oxidative stress, and inflammation, all of which impair insulin signaling, thereby blocking sugar from entering our cells. This starves cells of fuel, causing cell death.
A chronic increase in saturated fat levels in the blood is toxic to pancreatic beta cells. Fat breakdown creates a slew of toxic breakdown products... which impair insulin signaling, thereby blocking sugar from entering our cells.
This isn’t just the case for diabetics though. After we eat a meal containing saturated fat, our insulin sensitivity is reduced for the next three hours. A study conducted at the University of Toronto found that even for non-diabetics, whose pancreases should have been able to increase insulin secretion to match elevated blood sugar levels, insulin secretion failed to compensate for insulin resistance. This means that saturated fat impairs beta cell function within just hours of ingestion — whether we have diabetes or not.
Not all fats are equal. Saturated fats like palmitate, found mostly in meat, dairy and eggs, cause insulin resistance, but oleate, a type of monounsaturated fat found in avocados, nuts, seeds, and olives was actually found to improve insulin sensitivity. This is because monounsaturated fats are more likely to be detoxified or safely stored away. In fact, in a study conducted by Swedish researchers from Uppsala University, as people’s diets were shifted from animal fats to plant fats, their insulin sensitivity improved by a difference of over 20%.
But we’re in college — why should we even be concerned with diabetes? It’s a little-known fact that one third of adults in America are prediabetic, meaning their blood sugar levels are higher than normal. Without any intervention, prediabetes becomes type II diabetes in less than ten years. Even more alarming is the fact that after the age of 20, we will have all the insulin producing beta cells we’re ever going to have in our pancreas for the rest of our lives. If we lose them, they’re gone for good.
So, what does this mean for us? If we want to avoid becoming the one out of three adults in America to develop prediabetes, we must we wary of what we choose to put on our plates. Reducing refined sugar is important, but equal in importance is avoiding saturated fat in meat, dairy, and eggs, while focusing on whole, unrefined plant fats found in avocados, nuts, and seeds. Our health depends on it.