Screening for Coronary Disease is not what most people think.

Coronary artery disease is the most common cause of death in the United States and the world. Briefly, when someone has a heart attack, it is due to coronary disease. Cholesterol plaques are deposited in the lining of the coronary arteries, which deliver blood to the heart itself. This causes inflammation and damage to the arteries, and clots can form. When the clot occludes the flow of blood, a heart attack can occur, causing damage to the heart muscle and sometimes dangerous and fatal heart rhythms. Even if complete occlusion doesn’t happen, narrowing of the arteries can cause chest pain and weakness of the muscle, leading to heart failure.

Unfortunately, many people have no idea that they have coronary disease until damage is done. Sometimes, the first sign of the disease is sudden death from a heart attack or arrhythmia. Like most conditions, we would like to diagnose coronary disease early, while there is time to prevent the dangerous signs and symptoms.

Most people do not know what it means to screen for coronary disease. They think that the doctor listens to their heart, checks their cholesterol, and they’re good to go. That is not what I’m talking about. Listening to the heart does not detect early or even late coronary disease in most cases. Checking cholesterol levels is extremely important, but cholesterol levels are a risk factor for heart disease, not heart disease itself. There are many risk factors for coronary disease: cholesterol levels, diet, smoking history, family history, body weight, body fat distribution, and others. Even if you have multiple risk factors, you may never develop the disease, and some people with coronary disease have few if any risk factors.

Sidenote: I have heard people say many things about cholesterol. One is that they don’t understand how they had a heart attack since their cholesterol is fine. A similar statement is that they aren’t going to have a heart attack because they have normal cholesterol levels. Elevated cholesterol is a risk factor for heart disease, and treatment to lower cholesterol lowers the risk of heart disease. (This is definitely true, and anyone who says otherwise is mistaken or lying.) But people can have heart disease without having an elevated cholesterol. Risk factors are just that.

This is true with many conditions. Family history of breast cancer is a risk factor for breast cancer, but most women with breast cancer have no family history. Many people involved in serious car accidents are good drivers with a spotless record and no prior history of accidents. While most cases of lung cancer are in smokers, not all are. During my career in medicine, I saw many, many cases of coronary disease in people who did not expect it.

So, how do we screen? A person’s risk of a disease affects how we screen for it. For example, a teenager has an exceedingly low risk of prostate cancer, so we don’t screen at all. The same is true for breast cancer. Most young women should not be screened for breast cancer. People at very low risk don’t need screening. People who already have proven coronary disease need testing, but not the screening tests that we are going to talk about.

Let’s look at specific types of people. First would be people who are at very low risk and should not get screened. Tests are not perfect. Since a young, healthy person with no risk factors for heart disease (no family history of disease at a young age, and no genetic cholesterol problem) has such a low risk, false positive tests would actually outnumber any positive tests that were real.

We often screen people without symptoms who want to start an exercise program. They or their doctor may want to make sure they are safe to participate. A stress test may be a good choice. The patient walks on a treadmill in a standardized, progressively more difficult protocol, while an ECG is running. Sometimes, an ultrasound (echocardiogram) or nuclear imaging test is also performed. Certain changes on the ECG or imaging would indicate an increased risk of the patient having diseased, narrowed arteries. Further testing, such as a coronary angiogram, would then be performed to determine the extent of disease and whether treatment is indicated.

People with no symptoms but who are at significantly elevated risk may not need screening. They are so likely to have coronary disease that the doctor could just assume that they do have it. For example, they may have a markedly elevated LDL cholesterol and multiple family members with coronary disease. Aggressive risk factor modification would be instituted without further testing. This includes good blood pressure control, cholesterol-lowering medication (typically a statin such as rosuvastatin, which I take), and an exercise program. A stress test might be performed, as mentioned above, to see if they can tolerate such a program.

Perhaps the most common type of patient to screen is one where the risk of disease is intermediate. They may have a family history, but the cholesterol is not markedly elevated. A smoker without a family history may fit in this category. Here, a stress test would not be good enough. Remember, a stress test only detects advanced disease. A routine ECG would be of little help and is not recommended to screen for coronary disease, because there are many false positives and negatives. In this patient, a coronary artery calcium scan may be best, and it was the test I preferred when I was in practice.

The scan itself is simple. You lie in a machine for a few minutes. It is not enclosed like an MRI, and I have never heard of anyone becoming claustrophobic. There are no injections and essentially no risk. When cholesterol plaque is deposited, it is soft and uncalcified. Over time, the plaque calcifies, and you can see it on the scan. You will get a numerical score reflecting how much calcium is found in the lining of the arteries. The best is zero. That means that you have no detectable calcification in the coronary arteries. The percentile tells you how you compare to others your age.

A low score when you are young may be in a high percentile. That same score when you are older will put you in a lower percentile. If you are under 50, most people have a zero score. That could be because there is no plaque, but it could also mean that it is there but hasn’t calcified yet. Some specialists would recommend repeating the scan every five years or so until you are 60, giving the plaque time to become visible.

The calcium score scan doesn’t tell you if the arteries are narrowed, though the higher the score, the more likely it is that there is some narrowing. Even without narrowing, plaque can cause a heart attack, but narrowing makes heart attacks more likely. If your doctor suspects narrowing, they may order a stress test or a CT angiogram, a more detailed scan that shows narrowing. The CT angiogram is more expensive than the calcium scoring and requires injection of a contrast agent and more time in the scanner. The CT angiogram is not an appropriate screening tool for most people.

I found the calcium score test to be very helpful. For example, if you are 50, one of your parents had a heart attack in their 50s, but your cholesterol is fine, and you have no other risk factors for heart disease. You might consider a scan. If there is no plaque, your doctor may just repeat the scan in five years. If there is plaque, they may recommend a change in diet and start a statin to slow or prevent further plaque deposition. Statins reduce the risk of a heart attack and save lives.

Everyone wants to have a longer, healthier life, but we all want to live life to the fullest. Many people watch their diet and exercise, but otherwise ignore their risk of the most common cause of death. Talk to your doctor about screening for heart disease. Maybe you haven’t reached the age where any specific screening is needed. If screening is considered, ask if a calcium score is a good idea.

The best oils are the ones that you make healthy meals with.

If you keep up with the news, you’ve read about the debate about seed oils. Some people claim that seed oils are unhealthy, even poisons, because they may be inflammatory. They advise using animal fat, or tallow, instead of seed oils. Longstanding science has said that healthy plant-based diets that include unsaturated fats, are healthy, lowering the risk of heart disease and other chronic diseases.

The seed oils that are said to be the most dangerous are soybean, canola (rapeseed), corn, grapeseed, cottonseed, safflower, rice bran, and sunflower. Other oils made from seeds include flaxseed, sesame, almond, and walnut.

There are studies that suggest that some of the seed oils can increase levels of inflammation in the body. Chronic low-grade inflammation does have harmful effects, including autoimmune disease, heart disease, and cancer. However, there are few, if any, well-designed studies that show these harms occur more in people who consume seed oils. Most studies suggesting harm are in animals and at high doses. Even cottonseed oil, which is rarely defended as healthy, doesn’t appear to increase inflammation.

Numerous well-designed studies show that overall, unsaturated fats derived from plants and their seeds lower the risk of heart disease compared to animal fats. Rather than quoting and referencing hundreds of articles, I reference this superb review. Of note, the authors discuss inflammation and oxidative stress (another proposed risk of seed oils) and show the strong evidence that plant oils are not a cause of these problems. This study from 2025 shows that plant oils, including canola and soybean, lower the risk of dying of heart disease or cancer. I could go on and on. Unsaturated fats from plants, including seed oils, have unsaturated fats and clearly benefit human health.

For those of you who really want to learn about the science of fat and inflammation, I refer you to this article. It describes that both unsaturated and saturated fats can sometimes increase inflammation under certain conditions, such as the other foods the person is consuming.

A big problem with studies on fats is that rarely does someone eat only the fat being studied. And even if they do, something else always changes. If you take people who are eating a lot of olive oil and substitute canola oil for it, you may see something negative. But the apparent harm could be from the removal of olive oil. Replacing tallow and lard with plant oils has shown significant benefit. Some could be from the plant oils, and some from not eating the saturated fat. Regardless, you are better off.

The most important factors are what you eat the oils with and how you prepare the food. Over the last several decades, we have been eating far more seed oil than in decades past. Those against these oils blame the oils themselves. I don’t entirely dismiss that possibility, but we’ve also been eating far more ultra-processed food (UPF), which now represents more than half of the calories consumed in the United States. We know ultra-processed food causes inflammation, heart disease, diabetes, obesity, and cancer. Eating the high-calorie, high-sugar UPF is the cause of these conditions, not the plant oil. I bet if you made Twinkies and jelly doughnuts with olive or flaxseed oil, two of the healthiest fats known, people would still become ill.

If the rest of your diet is healthy, unsaturated plant-based oils are better for your health than saturated fats from meat. That is why the Mediterranean Diet is so good for you. If you use olive oil every day, you are better off than if you use tallow every day. If you believe you have evidence from well-designed human studies to the contrary, please email me.

If you want to be healthy, eat mostly plant-based oil. If you’re afraid of seed oils, though I think they’re fine, you can cook exclusively olive oil and avocado oil, as I do. Use avocado for high heat, and olive oil for everything else. You shouldn’t cook with flaxseed oil, but I add it to yogurt. It’s very healthy and makes it creamier. If you want to be as healthy as possible, don’t eat ultra-processed foods, regardless of the oils they contain.

One final point. Robert F. Kennedy, the Health and Human Services secretary, is pleased that some fast food chains are using beef tallow to make their french fries. I don’t have strong feelings about what a restaurant does, but the main point should not be their frying oil. The more important thing for your health is not to eat french fries. We know that frying food isn’t healthy, and french fries have a high glycemic index. With the other foods served at fast food restaurants, you’ll gain weight. Read my book. If you follow the Three Rules, you’ll lose weight. If you also follow the Mediterranean diet, with or without seed oils, you will be even healthier.

There are pros and cons, and we all have different ideas about what is important. My father will give up taste to avoid the slightest harm. Most people eat whatever they want and don’t think about it. If there are any harms in eating something, I recommend you consider these. Since I was in medical school thirty years ago, there has been a debate about eggs and heart disease.

Countless studies have looked at the risks of eggs, their effect on cholesterol levels, and whether that translates into harm. As an aside, there is absolutely a link between cholesterol and heart disease. Anyone who says otherwise is wrong or lying. It is not a perfect link. Neither is the link between seatbelts and death in a car accident. The risk of dying in a car accident is much higher than dying from an egg. (See a later post on hazard and risk.) Thankfully, we are not in many car accidents.

For most of my career, experts have claimed eggs are bad for cholesterol and cause heart disease. But, experts and dietary studies are far from perfect. 

One of the biggest problems with dietary studies is that it is difficult to look at the effect of a new food in your diet without removing something else. If you changed from frying in shortening, when it still had trans fat, to sunflower oil, you would see benefits. Was this from the sunflower oil? Maybe, but it was also from removing the shortening from your diet. The same thing happens with eggs.

If you look at egg eaters, they probably eat less of something else, say Cocoa Puffs. Another problem is what are called confounding variables. If you try to study whether eggs are good for you, you have to look at other foods the study group may be eating. Egg eaters may also be more likely to eat bacon or smoke. There are statistical methods to control for these variables, but they are imperfect (called residual confounding). 

Another problem with egg studies is the lack of knowledge about cholesterol. First, most experimenters have looked at total cholesterol and determined that eggs are rotten because they raise total cholesterol. But total cholesterol is not a good predictor of heart disease because there is LDL (often called bad cholesterol) and HDL (good cholesterol).

Over the last several years, we have learned about the subfractions of LDL and the function of HDL. Small LDL is particularly harmful because it more easily enters the wall of the coronary arteries. Large LDL is the opposite. HDL can aid in removing cholesterol from the artery walls, called cholesterol efflux. Some HDL performs this function better than others. Well, eggs are associated with lower levels of small LDL, higher large LDL, and improved HDL functioning. (See the study) 

So what about studies directly comparing egg consumption with heart disease? Some studies have shown harm, and more recent studies have been inconclusive or have even shown benefits. I have learned in medicine that if it takes many studies to prove harm or benefit, the effect if it exists, is likely to be unimportant. But, a recent meta-analysis, a study that combines many previous studies, suggests no harm and even some benefit of eating eggs. (See the study)

So, what is the truth about eggs? I wouldn’t eat five eggs every day, but within reason, eating eggs has little effect on coronary artery disease risk. A theme in my book, The Three Rules to Lose Weight and Keep It Off Forever, is to avoid being ridiculous. This applies to eggs. 5-10 a week or a bit more probably has little harm. 30 per week might. But remember, what you replace it with is important. If I replace eggs with tuna or sardines, that would be fine. If I replace it with Cap’n Crunch, you’d better watch your scale. As always, please talk to your doctor about your specific health issues and the risk of eggs.