Emerging evidence between cardiac amyloidosis and insulin resistance

The link between insulin resistance and heart problems is well known. Heart attacks, heart disease, and heart failure mortality have been steadily climbing for adults under 40 since 2018. But there are also underdiagnosed conditions that can be directly attributed to poor glucose control.

By this, I’m referring to cardiac amyloidosis.

A quick definition of cardiac amyloidosis

Cardiac amyloidosis, or more specifically transthyretin amyloidosis (ATTR), is the result of misshapen proteins in your blood. These are incorrectly formed proteins that your body can’t use. As they flow through your bloodstream, they gradually build up around your heart.

An increasingly large buildup can thicken the walls of your heart, which makes it more stiff. This forces it to work harder to pump the same volume of blood. This ultimately weakens the heart, disrupts your heartbeat (arrhythmias), and can eventually lead to heart failure and death. 

Doctors once thought that cardiac amyloidosis was a fairly rare condition. But modern studies show it’s far more common than first believed. Noninvasive testing shows a much larger number of patients in the US, and not necessarily due to age, gender, or genetics.  

The relationship between cardiac amyloidosis and insulin resistance

Research shows that metabolic conditions such as type 2 diabetes and insulin resistance are disproportionately prevalent in patients with ATTR. This means there’s a very strong link between ATTR and insulin response based on how the body responds to high dietary sugar intake.

Here’s a closer look at how the two intersect:

• Patients with cardiac amyloidosis are frequently diagnosed with hyperinsulinemia and elevated HbA1c levels (average blood glucose over the past three months).
• Unregulated insulin may encourage the development of amylin, which may increase the production of amyloid proteins, which are then deposited in your heart.
• Amyloid fibril-induced inflammation may increase inflammation in the body, which may lead to defective insulin signaling, among other things. 

Cardiac amyloidosis appears to be a deeply physical expression of the damage occurring due to insulin resistance. 

That means if you’re currently struggling with poor metabolic health, you may be encouraging (or worsening) a case of cardiac amyloidosis.

Could you have cardiac amyloidosis?

It used to be difficult to diagnose this condition. These days, however, there are a few non-invasive scans. If you’re unsure whether you should book one, here are some of the main symptoms of cardiac amyloidosis:

• Unexplained fatigue and weakness
• Palpitations or irregular heartbeat
• Swelling of the abdomen, legs, and other parts of the body
• Shortness of breath with both exercise and everyday activity
• Dizziness and lightheadedness

It’s also worth knowing that you’re at a much higher risk of cardiac amyloidosis if you’re dealing with insulin resistance.

You can learn more about the basics and how to address it in my guide on what it means to be insulin resistant.

The fastest way to resolve insulin resistance

There’s a clear bi-directional relationship between cardiac amyloidosis and insulin resistance. I could spend far more time here exploring each and every mechanism, but the most important mechanisms to consider are overlapping metabolic and inflammatory pathways.

The good news is, it’s possible to restore both.

Let’s take a closer look at how to do this below.

Adopting a low-carb diet

There are many different types of low-carb diets, so it’s easy to get lost in the weeds. But to make things simple, just focus on eating fewer carbs than you currently do now. You can take your pick from among keto, carnivore, and similarly low-carb options. You can get as granular as you’d like — I just want you to start somewhere. 

Some rules of thumb:

• Avoid added sugar (as well as being leery of artificial sweeteners)
• Substitute whole, real food for processed food
• Wear a continuous glucose monitor to track trends related to certain foods

Considering optional medication solutions

I’m a big believer in lifestyle changes before medications — pills aren’t the only way to treat chronic disease, after all. That being said, there’s evidence to suggest that drugs like GLP-1 agonists and SGLT2 inhibitors may benefit both insulin resistance and conditions like cardiac amyloidosis. 

Just be advised GLP-1 agonists come with their own complications and side effects, so be sure to speak with your doctor before making any rash decisions. 

Performing regular resistance training

Studies show that increasing muscle mass may help to reverse insulin resistance regardless of your current weight. You can address this with simple exercises and continuous movement throughout the day. This means you don’t need to schedule a single one-hour gym trip: short bouts of bodyweight exercises squatting can still improve muscle mass (even compared to barbell back squats). 

Another element to building muscle is losing body fat, especially if you’re already within an obese or morbidly obese classification. Studies show even a modest weight loss of 5% can improve insulin resistance from visceral fat.

Adjusting lifestyle choices that may impair insulin function

By this, I’m referring to common habits like:

• Alcohol consumption. This is commonly accepted and even (erroneously) encouraged for heart health. That said, you should know alcohol is not your friend. It’s not only a heavy risk factor for diabetes, but may also induce whole-body insulin resistance, among many other risk factors. I would be very careful about indulging here unless you want to prolong insulin resistance. You’re welcome to learn more about this in my introductory course to alcohol.
• Irregular sleep. Studies show that inadequate sleep may worsen glucose control in patients with existing type 2 diabetes. It can also elevate levels of free fatty acids in the blood, which may result in temporary pre-diabetic conditions for otherwise young, healthy individuals. Do your best to create a set sleep schedule and aim for somewhere between seven and nine hours of rest per night — whatever works best for your body.
• Smoking. There are many other reasons beyond insulin resistance to consider giving up smoking. But for the purposes of this argument, I’m focusing on the fact that smoking is associated with insulin resistance. It may also contribute to developing hypertension and diabetes, both of which contribute differently to insulin resistance.

Please know I don’t expect you to go cold turkey with any of these, especially not in a single day. But I do recommend creating a game plan to address each one, or partnering with a friend, coach, or partner to help you execute on an action plan.

Where we go from here

Even this far in, we’ve barely scratched the surface of cardiac amyloidosis. There’s quite a lot more to understand about its interplay with insulin resistance, including the mechanisms required to restore metabolic health.

So there’s no time like the present to learn as much as possible, starting with whether or not you’re at risk for developing the disease.

I invite you to complete my free metabolic health quiz to get a better idea of your overall risks.