Skip the Morning Bagel
Think your breakfast might not matter before that afternoon cholesterol test? Think again. Eating a high-fat meal before the test can raise triglyceride levels and skew the lipid profile, and sugary and fatty foods can cause drastic spikes in triglycerides, making the test results hard to interpret. High-fat foods like butter, cheese, and full-fat dairy products should be avoided, as should sugary foods like desserts, candy, and soda which can affect your results. Your doctor needs accurate numbers to assess your heart health properly, and that seemingly innocent cream cheese bagel could throw everything off. The American Heart Association (AHA) recommends that adults have a cholesterol test every four to six years, starting at age 20. What you eat the day before can affect cholesterol test results, as it’s traditionally recommended to fast for 9-12 hours before the test to get accurate results because recent meals can impact triglycerides and low-density lipoprotein (LDL) cholesterol levels.
The Fasting Debate Is Over (Sort Of)
Here’s something your doctor might not have told you yet – the old-school 12-hour fasting requirement has gotten more flexible. Standard practice used to require a person to fast for 9–12 hours before taking a cholesterol test, but recent guidelines have changed and now allow doctors to recommend nonfasting cholesterol testing to certain groups of individuals. Research involving over 300,000 people suggests that nonfasting tests are at least as accurate as fasting tests at predicting future cardiovascular health problems. The Journal of the American College of Cardiology say that people who aren’t taking statins may not need to fast before having their blood tested for cholesterol levels. However, people aged 20 years and older without a history of heart disease probably do not need to fast before a screening test, though people with a family history of heart disease may need to fast for accurate measurements. If you’re already on cholesterol medications, your doctor might still want you to fast for the most precise results.
Lean Proteins Are Your Friend
Good meal options include grilled chicken with steamed vegetables (lean protein paired with fiber-rich veggies) or quinoa salad with mixed greens and beans (a healthy mix of grains, greens, and legumes). Lean proteins like fish, chicken, or tofu help lower cholesterol, and whole grains are also great because they are filled with fiber, which helps control blood cholesterol. For instance, a dinner comprising grilled chicken, steamed veggies, and brown rice is ideal as this food helps manage cholesterol and triglycerides, thus boosting overall health. Your body processes these foods efficiently without creating the dramatic blood fat spikes that can mess with your test results. A balanced meal with complex carbohydrates, healthy fats, and fiber is needed. Think of it like preparing your car for an inspection – you want everything running smoothly, not revved up and unpredictable.
Fiber-Rich Foods Make the Cut
Oats are rich in fiber and help lower bad cholesterol, while fruits like apples, grapes, strawberries, and citrus fruits are high in pectin which can reduce cholesterol, vegetables like leafy greens, carrots, and bell peppers are good choices, and legumes like beans, lentils, and chickpeas provide essential nutrients. Whole grains such as oats and barley, lentils, nuts, and fruits are foods that can help improve cholesterol. A study from 2024 found that twelve weeks of daily lentil consumption improves fasting cholesterol and postprandial glucose and inflammatory responses. Recent research shows that eating oats also improved levels of triglycerides and high-density lipoprotein (HDL), the “good” cholesterol. These foods work like tiny brooms in your arteries, helping sweep away the bad stuff. Soluble fiber can bind with cholesterol in the digestive system and remove it from the body, while polyunsaturated fats can help lower LDL levels.
Say No to Fried Everything
Foods to avoid include fried foods like fried chicken or fries, fatty meats such as bacon and sausages, and processed snacks like chips and crackers which should be skipped to avoid skewing cholesterol levels. High-fat foods can cause a temporary spike in triglycerides which may affect lipid panel tests, and consuming fatty foods before the test may lead to artificially high readings of cholesterol and triglycerides. That crispy chicken sandwich might taste amazing, but it’s essentially sabotaging your health assessment. Foods which are rich in saturated fatty acids like beef, lamb, poultry, pork, butter and milk raise the LDL cholesterol levels and lower HDL cholesterol levels, excessive consumption of full-fat cheese and egg yolks should be avoided, plant fatty foods like palm oil, coconut oil and cocoa butter also tend to increase bad cholesterol levels, and foods which contain trans-fatty acids like fast food fries, cakes, cookies and pies can increase cholesterol levels. Eating foods high in saturated fats like red meats, butter, and high-fat dairy products can lead to higher cholesterol levels over time.
The Alcohol and Caffeine Trap
Alcohol can increase cholesterol levels, and caffeine may affect lipid metabolism and should be limited before the test. Drinking alcohol will cause a short-term increase in triglycerides (which will be screened for on a cholesterol test), so it’s best to avoid drinking alcohol 8 to 12 hours before a cholesterol test. You should not drink alcohol for 24 hours before the test. Even that single glass of wine with dinner or your usual morning coffee could throw off your numbers more than you’d expect. Heavy, regular drinking can lead to persistently high triglyceride levels, meaning the levels are high even when people haven’t consumed alcohol recently. While caffeine may not directly impact every test, it can increase stress levels, impacting cortisol levels and potentially other hormonal readings. Your cardiovascular system doesn’t need the extra stimulation when it’s being evaluated.
The Sugar Crash Effect
Sugary foods like desserts, candy, and soda should be avoided as they can affect your results. Blood sugar tests require you to fast because consuming sugar directly impacts glucose levels in the blood, so you should avoid sugary foods and beverages, as well as other high-glycemic index foods, before a blood test that involves checking glucose or insulin levels. You must avoid eating foods containing high levels of saturated fat, trans fats, and sugars the night before, as these increase cholesterol the following day. That afternoon energy drink or candy bar isn’t just giving you a sugar rush – it’s potentially creating false spikes in your blood work that could lead to misdiagnosis or unnecessary medication changes. Heavy, greasy, sweet foods are best avoided, as they affect your cholesterol levels. Simple carbohydrates can trigger inflammatory responses that temporarily alter your lipid profile.
Stay Hydrated, Stay Smart
Drinking plenty of water is important as staying hydrated supports your body’s functions and helps keep your blood sample clear, which can positively impact test results. Hydration is equally vital to stay hydrated before a cholesterol test, as hydration affects blood test results and is important for general health, and drinking enough water keeps your circulation healthy and guarantees that your body is operating at its best. Water doesn’t just help with accurate testing – it makes the blood draw easier for the technician too. Staying well-hydrated helps your body function optimally, and proper hydration can ensure that your blood sample is as clear as possible, positively impacting the test results. Think of water as the ultimate preparation tool – it’s free, it’s natural, and it genuinely helps your body perform at its peak during testing. Dehydration can concentrate certain substances in your blood, potentially skewing results and making you appear sicker than you actually are.
Timing Your Last Meal
Your healthcare professional might recommend drinking only water and avoiding food, other beverages, and certain medications for up to 12 hours before your test to ensure accurate results. According to the American Heart Association (AHA), fasting for 9 to 12 hours affects the results of your cholesterol test, however, people who are 20 years of age or older and have no prior history of heart disease are unlikely to require fasting prior to a screening test and can consume healthy food the night before the test. A fasting blood test may be necessary when the results of a non-fasting blood test indicate a triglyceride level of 400 milligrams per deciliter (mg/dL) or higher, as triglycerides are a type of fat in the blood and the foods that people eat can affect the level of triglycerides in their blood. For this reason, cholesterol tests are often scheduled in the morning so that you don’t have to spend a whole day hungry while waiting for your test. If you’re required to fast, your last meal should be light and eaten early enough to allow for the full fasting period.
The Exception Rule
What you eat the night before a cholesterol test won’t significantly change your test results because long-term dietary habits affect cholesterol, and it generally takes weeks to months for a change in diet to affect cholesterol numbers. What you eat the night before a cholesterol test doesn’t really affect the results because the food you eat affects your cholesterol more in the longer term, and it takes weeks to months for any diet changes to affect your cholesterol numbers. This might seem to contradict everything we’ve discussed, but here’s the nuance: while your overall cholesterol levels won’t dramatically shift overnight, the immediate effects on triglycerides and the accuracy of your lipid panel absolutely can be affected. Your low-density lipoproteins (LDL) — also known as “bad” cholesterol — may be affected by what you’ve recently eaten, and a recent meal may also affect your levels of triglycerides (another type of fat in your blood). Think of it like taking a snapshot – you want that picture to represent your true health status, not a moment when everything is artificially elevated from your last meal.
What’s the one thing most people never consider before their cholesterol test that could completely change their results?
