Intermittent Fasting and Hashimoto’s

Intermittent fastingIntermittent fasting is an approach to timing your meals that has grown in popularity. Recently a number of people have asked my opinion about doing it if you have Hashimoto’s.

Like all things Hashimoto’s related, this is a complicated question masquerading as a simple one.

How does Intermittent Fasting (IF) Work?

IF is not really a diet, it’s more of an eating pattern where you cycle between your regular meal pattern and fasting (not eating at all).

The focus is not on what foods you should eat, it’s more on when you should eat whatever is you choose to eat.

If you have been following me for any period of time you will know that I believe what you eat makes a huge difference if you are trying to heal. And the reason is simple: Hashimoto’s is an autoimmune disease and an estimated 70-80% of our immune system lives in our digestive tract.

So what you eats matters, in a big way. It also turns out that deciding not to eat can also have major impacts on your health.

The question today is what are the pros and cons of intermittent fasting with regards to Hashimoto’s and hypothyroidism.

What’s the Point of IF?

The reason IF has become popular is that it has been shown in some research to have a number of health benefits.

Basically, there are three major mechanisms that have been identified as benefits of intermittent fasting:

  • 1. Increased insulin sensitivity and mitochondrial energy efficiency – Fasting increases insulin sensitivity and improves energy production from mitochondria (your body’s energy factories), this slows aging and disease and helps with weight loss.
  • 2. Increased capacity to resist stress, disease and aging – stress isn’t always bad. Fasting causes a stress response inside cells (kind of like exercise). This causes genes to be expressed that help your body better cope with stress.
  • 3. Reduced oxidative stress – fasting helps reduce free radicals inside your cells and prevents damage from them.

This All Happens in People Who Don’t Have Hashimoto’s

Before you get all excited, it’s important to understand that people with Hashimoto’s are not normal subjects.

They often don’t have normal insulin responses, their immune systems are hyper-vigilant, and they rarely have a normal capacity for handling additional stress.

It’s important to understand is that intermittent fasting can help you under some circumstances and can actually do some harm in others.

Preserving Your Circadian Rhythm Trumps Everything Else

The more I study physiology and look at the connections between systems of the body, the more I realize how incredibly important respecting your body’s natural clock is.

This is one of those areas that can have a profound impact on your health and well being and on the progression of your Hashimoto’s.

Your body’s natural clock regulates your hormones, affects your ability to digest food and absorb nutrients, affects immune function, eliminates toxins, and helps regulate your insulin and stress responses.

If this system is out of whack it can result in you not sleeping properly, having digestive issues and constipation, craving sweets and carbs, having trouble losing weight and having a really hard time handling stress (Sound familiar? These are super common Hashimoto’s symptoms).

These chronic disruptions of your circadian rhythms are pretty much ignored by proponents of intermittent fasting.

Eating times are either random or just plain wrong. This can have huge consequences when you have Hashimoto’s and autoimmunity. You can not overlook the relationship between meal times and your body’s internal clock, especially if you need to restore that rhythm.

When Are the Best Times To Eat?

Your body is actually programmed to eat at night. The Autonomic nervous system operates around your circadian clock.

During the day your sympathetic nervous system puts your body into an energy burning mode, whereas at night your parasympathetic nervous system puts your body into an energy replenishing relax and sleep mode.

This is why normal cortisol peaks in the morning and gradually diminishes and melatonin peaks at night.

Unfortunately, this system is highly sensitive to getting disrupted, especially when you have autoimmunity and hypothyroidism and none of your body’s systems are functioning properly.

So, if you eat at the wrong times when having a large meal during the day, you can cause insulin surges and this can totally mess up your autonomic nervous system.

This can result in you inhibiting your sympathetic nervous system and turning on your parasympathetic nervous system which makes you feel tired and fatigued during the day.

And instead of spending energy and burning fat, you’ll store energy and gain more fat. This is a downward spiral and the ultimate no win situation.

The problem with many intermittent fasting programs is that they don’t pay any attention to this at all.

Another thing that is really important with Hashimoto’s is blood sugar balance. I have written pretty extensively about this here.

The impact of fasting on a pre-existing blood sugar imbalance must be considered whenever you’re considering doing IF. I CANNOT OVERSTATE HOW IMPORTANT THIS IS!!!!

Let’s Breakdown Some Common IF Programs. Here are the most common approaches that I could find:

ALTERNATE DAY FASTING: Followers of this program eat on some days and don’t eat at all on others. This is really hard to do and can result in a major surge in hunger (obviously).

If you do this and then binge eat, you are pretty much guaranteeing a massive insulin surge. This will cause a cortisol surge which can result in LH and FSH suppression by the pituitary, problems with liver detoxification, under conversion of T4 into T3, thyroid hormone receptor resistance and suppression of SIgA and a breakdown of immune barriers.

If you are hypoglycemic, your blood sugar will crash dangerously and you might wind up feeling major fatigue, having insomnia, getting irritable and/or depressed, slowing your metabolism so that losing weight will be harder, getting headaches and hormonal imbalances. Not good.

There are reports from people who have tried this that they experience sleeping disorders, constipation and persistent fatigue. In other words, an absolute disaster for people with Hashimoto’s.

ONCE A WEEK OR TWICE A WEEK FASTING: A little easier to do than alternate day fasting, but the problems mentioned above still persist. Coming off of it can generate massive insulin surges and hypoglycemics will suffer in a big way.

FASTING EVERY OTHER WEEK OR EVERY MONTH: This is even worse than once or twice a week and basically it’s an attempt to create an easy fast program. Half measures almost never result in half successes in my experience, they result in disappointment and failure.

SKIPPING DINNER: This totally goes against your body’s natural rhythms. If you’re hypoglycemic you’re just prolonging the punishment and the damage.If you are insulin resistant you may once again wind up with an insulin surge when you have breakfast.

This can also make sleep problems worse. People who are in favor of this approach say that breakfast is a very important meal and should not be skipped.

I agree, but most Americans have a breakfast that is heavily weighted towards sugar and carbohydrates. That is a recipe for insulin surges and a day filled with misery.

SKIPPING BREAKFAST: Some people feel that this is better than skipping dinner. Especially if you exercise in the morning. But this also can cause problems.

Again, if you are hypoglycemic you will not have had anything for 6-9 hours – fasting is technically the gap between meals minus digestion time – so even though you don’t eat for 12-16 hours you’re actually fasting for 6-9 hours.

No matter how you calculate it, that’s just too long.

What’s the Best Approach?

For hypoglycemics or people with Hashimoto’s who have a mixed presentation of hypoglycemia and insulin resistance, I think it’s far more important to work to balance blood sugar and to restore and preserve circadian rhythms.

In my experience that will make you feel much better, help you to have enough energy to exercise and be active and get you in a position to actually lose weight. 

And your choice of foods is also very important. Eating foods that are high in nutrient density and avoiding inflammatory foods like gluten, dairy and non-fermented soy is also much more important than fasting for reducing systemic inflammation.

Is There A Fasting Approach That Can Work for People With Hashimoto’s?

It really depends on how bad things are and where you are in the progression of the disease. If you have major disruptions in your circadian rhythms and you have major imbalances in blood sugar, I would strongly discourage attempting the intermittent fasting programs.

In my experience most people who have Hashimoto’s that come for treatment are advanced enough where intermittent fasting just doesn’t give you enough benefits for all the serious downsides that may result.

If you have healed to the point where you have restored your circadian rhythms and you blood sugar is well balanced then perhaps the One Meal Per Day Fast could be something that you could attempt.

The is really the only viable option for keeping balance of your body’s clock and maximizing the beneficial effects of intermittent fasting. If you exercise, you’ll need to feed your muscles post workout with a low glycemic index recovery meal to avoid the dangers of insulin surges.

And having proteins and carbs before your workout that are quickly assimilated can help load glycogen in your muscles, nourish the fast fibers in those muscles and help boost max strength and performance.

With Hashimoto’s, however, this is another potential land mine as the most commonly recommended form of protein is good quality whey protein and while whey is refined and filtered it can contain trace amounts of casein which can cause major immune flare ups in some Hashimoto’s folks.

Check out this post to learn more

Bottom Line:

In my opinion, intermittent fasting can have some health benefits for people whose Hashimoto’s is very well managed and who have balanced blood sugar and well respected and preserved circadian rhythms.

Unfortunately, the reality is that most people with Hashimoto’s have not achieved anything close to that in their lives and many have some degree of circadian disruption and some degree of blood sugar dysfunction.

For them, working to restore their body’s natural clock and to keep their blood sugar stable throughout the day is much more important than jumping on the IF bandwagon.

Daily focus on those two goals (body clock maintenance and blood sugar balance) is a much better use of your money, time, and energy and will yield much better long and short term results like more energy, better sleep, better digestion and a happier mood and outlook on life.

References: IF research overview IF and insulin sensitivity Review of trials IF

About the Author Marc Ryan

So now, not only is it my profession, it’s my passion, and it’s personal. I’ve been joking with people lately saying it’s a blessing and a curse. A blessing because I really get it, and a curse because I really got it! ?

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