If your doctor has recommended lowering your cholesterol, you're not alone. Cholesterol is perhaps the most well-known health biomarker, especially for people managing diabetes. Its connection to cardiovascular disease has been discussed for decades, yet it remains one of the most misunderstood aspects of health. The good news? Recent scientific understanding has shifted dramatically from what we thought we knew, and diet can play an important role—just not in the way you might expect.
Understanding Cholesterol: The Basics
Before we dive into what you can eat, let's clarify what cholesterol actually is. Cholesterol is a lipid—a type of fat—that's primarily produced by your liver. It travels through your bloodstream as part of lipoproteins, which are essentially tiny packages that transport cholesterol to cells throughout your body.
Your body uses cholesterol for essential processes, including:
- Building and maintaining cell membranes
- Producing hormones like estrogen and testosterone
- Creating bile acids that help digest food
- Synthesizing vitamin D
Cholesterol isn't inherently bad—in fact, you couldn't survive without it. The problem arises when you have too much LDL cholesterol (often called "bad" cholesterol) circulating in your blood. High LDL levels can contribute to plaque buildup on artery walls, increasing your risk of heart attack and stroke. This risk is particularly important for people with diabetes, who already face elevated cardiovascular disease risk.
The Dietary Cholesterol Myth: What Science Really Shows
For nearly half a century, doctors advised patients to limit dietary cholesterol—the cholesterol found in food—to less than 300 mg daily. This meant restricting eggs, processed meats, shrimp, and full-fat dairy products. Many people dutifully avoided these foods, believing they were protecting their hearts.
But here's what current research tells us: cholesterol from food has little to no impact on blood cholesterol for most people. This surprising finding has revolutionized our understanding of cholesterol management.
Why doesn't dietary cholesterol raise blood cholesterol as much as we once thought? Your body is remarkably intelligent. When you consume more cholesterol from food, your body activates compensatory mechanisms:
- It increases cholesterol excretion through bile
- It decreases cholesterol synthesis in the liver
- It adjusts absorption rates in the intestines
This internal regulation system keeps blood cholesterol relatively stable for most people, regardless of how many eggs they eat for breakfast.
The Exception: Cholesterol Hyper-Responders
About 15-25% of the population are "hyper-responders"—people whose blood cholesterol does respond more dramatically to dietary cholesterol intake. If you're in this group, eating high-cholesterol foods will raise your LDL cholesterol more than average.
However, even this finding comes with nuance. Studies suggest that in hyper-responders, both LDL and HDL cholesterol may rise equally, and the size of lipoprotein particles may increase. Larger particles are generally considered less harmful than smaller, denser particles, potentially mitigating some cardiovascular risk.
Low-Carb and Ketogenic Diets: A Complex Relationship
Many people with diabetes explore low-carbohydrate or ketogenic diets for blood sugar management. But what about cholesterol? The effects are surprisingly varied and not entirely predictable.
Research shows different outcomes for different people:
- Some people experience no change in LDL cholesterol levels
- Others see LDL cholesterol decrease alongside improvements in triglycerides and HDL
- A subset—particularly "lean mass hyper-responders"—experience significant LDL increases
Interestingly, some studies have found that low-carb diets may help transform LDL cholesterol particles into larger, more benign forms. This particle size matters because smaller, denser LDL particles are more likely to penetrate artery walls and contribute to plaque formation.
Important recommendation: If you're transitioning to a low-carb diet, get baseline blood lipid testing before you start and schedule periodic follow-up testing. This allows you and your healthcare provider to monitor your individual response and make adjustments if needed.
Diet Still Matters: Focus on These Beneficial Foods
While dietary cholesterol may not be the villain we once thought, diet absolutely still matters for cholesterol management. The key is shifting focus from avoiding cholesterol to embracing foods that actively support cardiovascular health.
Soluble Fiber
Soluble fiber binds to cholesterol in your digestive system and helps remove it from your body before it enters your bloodstream. Excellent sources include:
- Oats and oat bran
- Beans, lentils, and chickpeas
- Brussels sprouts and broccoli
- Apples, pears, and citrus fruits
- Psyllium husk
Omega-3 Fatty Acids
These healthy fats help lower LDL cholesterol and triglycerides while supporting overall cardiovascular health. Find them in:
- Fatty fish like salmon, mackerel, sardines, and herring
- Walnuts and flaxseeds
- Chia seeds
Phytosterols and Antioxidants
Plant compounds called phytosterols can block cholesterol absorption, while antioxidants prevent cholesterol from oxidizing—a process that makes it more harmful. These beneficial compounds are abundant in:
- Nuts like almonds, pistachios, and pecans
- Colorful vegetables and fruits
- Whole grains
- Legumes
- Extra virgin olive oil
The message here is important: carbohydrates aren't the enemy. Whole and minimally processed carb-containing foods like fruits, vegetables, legumes, and whole grains provide essential nutrients and compounds that support healthy cholesterol levels.
Beyond Diet: A Holistic Approach to Cholesterol Management
While dietary changes can positively impact cholesterol levels, the most effective approach addresses multiple lifestyle factors simultaneously. For people with diabetes, this comprehensive strategy often yields the best results for both blood sugar and cardiovascular health.
Exercise Regularly
Physical activity is one of the most powerful tools for improving your cholesterol profile. Exercise can raise HDL ("good") cholesterol while lowering LDL and triglycerides. Research suggests that combining aerobic exercise with resistance training may be most effective.
Try these activities:
- Brisk walking (aim for 30 minutes most days)
- Jogging or running
- Cycling
- Swimming
- Resistance training with weights or resistance bands
Limit Alcohol Consumption
Heavy drinking increases triglyceride levels and can raise cholesterol. Similar to excess sugar intake, too much alcohol contributes to fatty liver buildup, which interferes with normal cholesterol clearance and metabolism. If you drink, do so in moderation—or consider eliminating alcohol entirely for optimal metabolic health.
Quit Smoking and Vaping
Smoking and vaping can lower beneficial HDL cholesterol levels. Smoking also contributes to free radical production and oxidative stress in your body, which makes LDL cholesterol more dangerous by promoting oxidation. If you smoke, quitting is one of the single most important steps you can take for cardiovascular health.
Consider Medication When Appropriate
Sometimes lifestyle changes alone aren't enough to reach target cholesterol levels, especially for people with diabetes who face elevated cardiovascular risk. Your doctor may suggest supplementing lifestyle modifications with cholesterol-lowering medication like statins. This isn't a failure—it's a practical approach to protecting your health when diet and exercise need additional support.
The Bottom Line
The relationship between diet and cholesterol is more nuanced than we once believed. For most people, the cholesterol in food has minimal impact on blood cholesterol levels. However, diet still matters tremendously—just in different ways than we thought.
Focus on:
- Eating foods rich in soluble fiber, omega-3 fatty acids, and antioxidants
- Including whole, minimally processed carbohydrates
- Monitoring your individual response, especially if trying a low-carb diet
- Combining dietary changes with regular exercise
- Avoiding smoking and excessive alcohol
- Working with your healthcare provider to determine if medication is appropriate
For people with diabetes, managing cholesterol is a critical component of reducing cardiovascular disease risk. The good news is that many of the lifestyle factors that improve cholesterol—like eating whole foods, exercising regularly, and maintaining a healthy weight—also support better blood sugar control.
Remember that everyone's body responds differently to dietary changes. What works for one person may not work the same way for you. Regular testing and open communication with your healthcare team will help you find the personalized approach that works best for your unique situation.
References
- Soliman, G. A. (2018). Dietary Cholesterol and the Lack of Evidence in Cardiovascular Disease. Nutrients, 10(6), 780. https://doi.org/10.3390/nu10060780
- Arnett, D. K., et al. (2019). 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation, 140(11), e596-e646. https://doi.org/10.1161/CIR.0000000000000678
