On Nutrition

In your younger years, how often did you cram for an important test? I know I’m guilty of that one (freshman year History of Western Civilization, I’m looking at you). While shortcuts are great in many areas of life, they’re not so great for actually absorbing information, or when taking a test that may provide important information about your health.

Someone I was talking to recently mentioned that they were having bloodwork done to check their cholesterol and triglyceride levels in a few days. Their previous test results weren’t great, and they were worried that the results on their upcoming test would be worse, since they hadn’t made any diet or lifestyle changes. “Is there anything I can do in the next few days to make my results better?” they asked. “No, not really,” I said. I should have added, “Why would you want to?”

This wasn’t the first time I’ve been asked how to “cram” for a cholesterol test. Many people, consciously or unconsciously, seek their doctor’s approval. No one likes to get a “failing” grade on their cholesterol test, but even if you could cheat on your test by making last-minute changes you don’t plan to sustain, you would only be cheating yourself.

Cholesterol is a waxy, fatty substance in your body that travels through your bloodstream via lipoproteins. Some is good — which is why our bodies actually make cholesterol — but too much is a risk factor for heart disease. Low-density lipoproteins (LDL), commonly called “bad” cholesterol, transport cholesterol to your body’s tissues and blood vessels, depositing any excess along the walls of your blood vessels. High-density lipoproteins (HDL), or “good” cholesterol, transport this excess cholesterol away from your blood vessels so it can be removed from your body. Triglycerides are fats that circulate in your bloodstream. High triglycerides and low HDL increase your risk for heart disease and Type 2 diabetes.

Your cholesterol levels are affected by what you eat over time, and any improvements to your diet and lifestyle habits generally take three to six months to have an effect, if they’re going to — some people see better results than others. Improving your diet and increasing physical activity can both lower LDL and triglyceride levels, but exercise does much more than diet for improving HDL numbers.

What about fasting before your blood test? It used to be standard practice to have everyone fast for up to 12 hours before a cholesterol test, but guidelines have changed recently. Whether you need to fast prior to the test depends on your individual risk factors, so follow your doctor’s instructions. Regardless of whether you need to fast, avoid alcohol for 24 hours before your test and don’t eat a fatty meal the night before — these two things could artificially raise your triglyceride levels.

As for long-term changes, start by eating less saturated fat — especially from fatty cuts of meat and processed foods — and increasing fish meals to twice per week. Go for more fiber-rich carbohydrates — whole grains, beans and lentils, vegetables, fruit — and fewer “simple” carbs such as sugar and white flour. Watch alcohol intake, especially if your triglycerides are high, because alcohol dramatically increases triglyceride levels in some people. If you like having a framework to guide your eating choices, the DASH diet (Dietary Approaches to Stop Hypertension) and the Mediterranean diet both encompass these suggestions. And if your physical activity levels aren’t what they could be — perhaps due to the pandemic — make a plan for gradually, steadily and consistently getting up and moving more.