Understanding Carbohydrates and Increased Cardiovascular Risk
Do you think saturated fat is the biggest risk factor for cardiovascular disease? Do you also think that carbohydrates, like the advertised heart healthy whole grains, should be the basis of your diet?
You’re not alone, and we’re going to dig in to why these widely accepted statements are harming your health and can put you in an early grave.
We’re going to look at why elevated blood glucose and insulin from carbohydrates in the diet is one of the greatest health risks the modern world faces.
You’ll see the research that points directly to carbohydrate rich diets being the driver for cardiovascular risk.
A diet that focuses heavily on carbohydrates leads to inflammation through your whole body, causes oxidative stress, and damages tissues. This leads to decreased function and declining health. Ultimately this kind of diet leads to chronic illness and a decreased lifespan.
The stabilized blood sugar and insulin on a lower carbohydrate diet promotes cardiovascular health and reduces the damage to tissues that can cause chronic disease and impaired organ function. This way of eating can lead to a healthier, longer life, and that’s something all of us want.
Let’s take a look at a real-life example for a moment. We’re going to talk about Nick, someone who I care deeply about.
Nick had a hard life. He was raised just after the Great Depression, so his parents had values that revolved around saving money and resources. This included cutting down on the grocery bill as much as possible. What food was cheap? Carbs. Bread, pasta, rice, and potatoes were the basis of his diet from when he was born until, well, now. It was ingrained in him that food should be as cheap as possible and existed only to fill the belly.
The vast majority of his generation and economic status share his sentiment, and that’s one of the reasons we have such large stacks of data to draw from when it comes to looking at the health risks of a diet based on carbohydrates.
In Nick’s case, he spent most of his life with a puffy belly. He wasn’t morbidly obese, but he was overweight and out of shape.
One day, when he was 44, he had a massive heart attack. Then a couple more while he was at the hospital, and another one a few years later. He had a quadruple bypass, replacement mitral valve, and pacemaker/defibrillator implanted.
He’s continued with his typical American style diet and his health continues to decline. Treats didn’t come often in his childhood, so now as an adult he freely indulges in chips, candies, and cakes as often as he likes, which is every day.
He now suffers with arthritis, osteoporosis, persistent inflammation and pain, dramatic cognitive impairment, worsening mental health, slow wound healing, and mobility challenges.
Nick’s story is all too common, and much of his difficulty and declining health could be turned around by choosing a more healthful and nutrient dense way of eating. Nick is a real person, by the way. I’ve just changed his name to protect his privacy. And I truly wish he was willing to change his food choices. His suffering is completely unnecessary.
Does a high fat or Ketogenic Diet cause heart disease?
The body is remarkable at healing itself when the right nutrients and fuel are present, and when the ones that cause ill health are removed.
When I first started looking into a ketogenic way of living, one of my primary concerns was a possible increased risk of heart disease. I hadn’t yet learned what I know now about how the body works and how impactful the right dietary plan could be.
Back then, I was worried all the saturated fat and meat in a ketogenic diet could be a problem, based on the prevailing lipid hypothesis of heart disease.
Back then I didn’t have the vast body of research under my belt that I do now. Today, I can confidently say that by choosing keto and virtually eliminating carbohydrate foods from my diet, I’ve dramatically reduced my risk of cardiovascular disease, and I’m going to show you why.
I’ll start off with the 3 best quotes out of this study which gathered dietary and health data from 42 European countries: (1)
“The most significant dietary correlate of low CVD risk was high total fat and animal protein consumption.”
“…the most significant correlates of high life expectancy: total fat and animal/total protein…”
“The most significant positive correlate of CVD risk is the proportion of [carbohydrate] energy…”
This study and more like it are showing that it’s the carbs in the diet that are contributing to heart disease. The above referenced review analyzed data from 1995 to 2008. The findings run contrary to the standard dietary recommendation that bases meals on carbohydrate foods. The conclusion was that carbohydrate consumption is the most correlated risk factor for cardiovascular disease. Researchers point out that the high glycemic load of these foods, or, how much they spike blood sugar, causes inflammation and increased circulatory insulin in addition to higher blood sugar levels. (2)
Eliminating the carbohydrates from the diet immediately decreases these risk factors. A ketogenic diet, which focuses on whole foods such as vegetables and animal proteins is one of the best, easiest, and most delicious ways to improve your cardiovascular health.
Carbs cause immediate arterial damage
A study out if Israel by Dr. Michael Shechter performed “reactive brachial testing” to groups of students fed varying diets. This testing uses a device like a blood pressure cuff to measure changes in artery structure in real time. Each student was tested before their experimental meals. After their meals, he tested them again. He found that the high carb intake groups experienced impaired function of their arteries. This negative impact is a direct and immediate consequence of the carbs many people eat multiple times a day. (3)
This study is most interesting because it shows immediate damage, which is something we haven’t been able to measure for until recently. For many years we’ve been collecting long term data with some short term metrics, such as tracking blood glucose periodically after meals.
This adds to the body of research we have on persistently elevated blood glucose being connected to heart disease risk.
Linking diabetes and heart disease
Looking at those with diabetes, you begin to see even more connections. Shechter’s study points to persistent endothelial damage, which is the tissue lining the arteries. We know that diabetics suffer with impaired circulation. Extreme cases where patients have lost too much circulation in their limbs require surgical intervention, often removing the affected body parts. One of the biggest mechanisms of damage is the increased blood glucose that comes from eating these sugary and starchy foods.
It’s not a failure of the body per say, the body is only reacting to what we do to it. Our tissues can only handle so much before they become damaged and function less well, and eventually lose function entirely. This is essentially what’s behind type II diabetes. Too many carbohydrate foods too often overwhelm the body’s ability to manage blood glucose via insulin secretion. Tissues respond less well to the insulin that’s secreted, and it becomes a vicious cycle. This burns out the beta cells in the pancreas that secrete insulin leading to ever-higher blood glucose concentrations and the need for injectable insulin in progressively greater amounts. (4)
The link between diabetes and heart disease is so clear that a diabetic diagnosis automatically doubles cardiovascular risk over the rest of the population.
Much of this risk comes from complications of hyperglycemia, the high blood sugar seen in diabetic patients. High blood sugar and increased insulin load damage the arteries both immediately, as seen in the above study, and over time, causing more and more degradation of the tissues.
The root of clogged arteries
What was once less understood about the cholesterol involved in atherosclerotic plaques is now becoming clearer: these cholesterol molecules are being used to patch microtears in the artery walls, preventing an immediate internal bleed. The more the arteries are damaged, the more cholesterol is used to patch the tears, and the more accumulation can be seen. It’s because of this process that plaques can get so thickly layered they block arterial blood flow and cause heart attacks.
Blaming cholesterol in the arteries for heart attacks is like blaming a fireman for a fire: it’s there to address the problem that’s already present.
If we shift from looking at the symptom, the cholesterol buildup in the arteries, to looking at the source, why it’s building up in the first place, we’ll land back on the inflammation and damage caused by persistent high blood sugar and insulin load in diets high in carbohydrate foods. (5)
Where did we go wrong?
Let’s rewind a bit to the origin of the lipid theory of heart disease. This theory was put out in the 50’s after popularized work by Ancel Keys. He was the major promoter of the theory that stated that elevated cholesterol from dietary saturated fat was the driving factor of heart disease. His ideas spread like wildfire. At the same time, John Yudkin was doing parallel research that showed it was sugar intake that was responsible for heart disease. Both of these scientists had observational research behind their work, yet Yudkin was largely ignored.
Three things cannot be long hidden: the sun, the moon, and the truth. With plenty of evidence over the last 70 years that saturated fat isn’t the villain it was painted as, such as persistent narrowing of the arteries, increased rates of diabetes, and increased cardiovascular risk despite decreases in saturated fat intake, researchers have continued to dig for answers.
We’ve looked at the persistent elevated blood glucose in those with diabetes. What if you don’t have diabetes or prediabetes? Turns out the blood sugar spikes after eating carbs are still a problem. The Whitehall study involved a large cohort of participants, 17,869 male non-diabetic civil servants, and collected data over 33 years. (6)
Blood sugar spikes in non-diabetics is also a risk
This study looked at participants’ blood glucose 2 hours after a 50g dose of sugar. That’s a little more than is in one can of soda. The blood sugar range varied among participants at that 2-hour mark, and the results showed that as that measurement increased, cardiovascular risk increased at about the same rate. The study authors were remarkably thorough in referencing additional work that comes to the same conclusion.
Glucose intolerance, or, when blood sugar remains high for too long after eating, is being highlighted in this study as a primary driver of cardiovascular disease.
There are a few mechanisms behind this. One is that glucose intolerance is tied to insulin resistance, which often develops in parallel with high blood pressure and the growth of atherosclerotic plaques.
Another mechanism is the oxidative stress and advanced glycation end products (or AGEs) that can accelerate exponentially when blood sugar is only slightly raised. Nick’s puffy belly is a perfect example of the inflammation caused by this process. Yes, it’s essentially excess adipose tissue, but the type and condition of this tissue is due of these drivers of inflammation. There’s an old joke among doctors that if a patient’s belly enters the exam room before the rest of them, they’re a heart attack waiting to happen.
What can I do to improve my health?
All carbohydrate foods are offenders in this context, but the worst ones are the highly processed foods that are easy to store and cook. Think breads, cereals, pasta, cakes, candies, and other sweet or starchy foods that are exceptionally easy to overeat. If you can’t eliminate all carbohydrate-heavy foods from your diet all at once, focus on the highly refined ones to remove first. This will make the biggest difference in your health in the shortest time.
Your food choices are in your control, and you can improve your health by choosing nutrient dense foods that don’t spike blood sugar and completely avoid the damaging reactions in the body that lead to increased disease risk.
We’ll dig in to the cardiovascular benefits of choosing a low carbohydrate diet in another section, since this is a lot to absorb. Leave your questions below to open the discussion and expand understanding.