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Why Intermittent Fasting doesn’t always work

By Lucy Rose Clinic

October 8, 2020

Intermittent Fasting is hugely popular right now, and many people get amazing results from doing….unless they DON’T.

Have you tried it before only to discover that you didn’t lose weight, but instead just felt miserable?

What is IF?

IF stands for Intermittent Fasting.

There are many approaches to it, but what all diets have in common is having a period of time where no food is eaten. Usually water or other liquids are allowed in the fast period. The fast period can be anywhere from 12 hours, to 30 days!

Fasting has been performed mostly for religious purposes for several thousand years, and appeared in the medical literature over 1 century ago. Humans evolved with natural periods of feast and famine for the majority of our history, and we all have genetic flexibility inherent from birth. However, that flexibility declines as we age and our body has to deal with a variety of factors such as constant high calorie diets, too much sugar and carbs, inflammation, elevated stress, and subsequent nutrient deficiencies and toxin loads.

Many studies have been done on the benefits of IF and there are some astounding results such as weight loss, improved blood sugar, boosted brain function and increased longevity.

There are also some associated risks and side effects. As a result, it is not right for everyone. Potential side effects and risks include: hunger, weakness, and tiredness.

it is impossible to say whether or not fasting is right for you, there are some definite risks that you should be aware of before you venture out onto an intermittent fasting experiment. Any diet changes should be discussed with your health practitioner and if you discover changes in symptoms when on a new program, report it back to your health practitioner immediately for support.


If you dramatically decrease your calorie intake, your thyroid will respond by releasing less thyroid hormone. This is a natural way of your body responding to what it thinks might be a famine or state of uncertain food intake. This means that your metabolism slows down, and is one reason people put on weight once they start eating more again, especially if returning to eating in a ‘binge’ fashion to make up for all the meals they lost!

Lower thyroid hormones than normal can lead to fatigue, mood changes, and feeling tired all the time.

Given that so many women has an undiscovered thyroid problem, it is not surprising that many women report that IF doesn’t work for them.

  • 40% of women right now have sub-optimal thyroid hormones and DON’T KNOW IT!

Stress Hormone Imbalances

Research confirms that fasting induces higher levels of cortisol in women. In addition to being more stressed, being hungry due to fasting can also make you moody!

Most women we see have an adrenal hormone imbalance, with either too little or too much cortisol being released every day. This happens from our modern lifestyles, not taking down time, and not adopting a stress management plan in your day if you are stressed. And who isn’t stressed?

This ties into exercise – if you have cortisol dysregulation, too much or too little exercise will work for or against you. The best way to know is with a 3-point cortisol test reviewed by a holistic practitioner.

Blood Sugar Imbalances

Hypoglycemia is low blood sugar, and the risk of it increases the longer you go without food. Some people simply don’t do well if they go longer than 8-10 hours without food. And, if you already have blood sugar issues, then there is an increased risk of low blood sugar with fasting.

Functional testing to check your blood sugar system should include:

  • Fasting insulin
  • Fasting glucose
  • HbA1C – shows three-month average of blood sugar – very handy if you have been fasting to check how it is affecting you.
  • 1,5 Anhydroglucitol – a validated marker of short-term glycemic control.

Not sure? Try this first

So you’ve read this article and now you think that fasting may not actually be right for you. The first step is to get some functional testing and an appointment to review results and set up a strategy. And strategies may need to be revisited and changed as you go along. This is actually very normal.

These suggestions are are very safe and generally beneficial for thyroid patients, but of course, consult your health practitioner before making any drastic changes to your diet;

  • Eat 3 meals a day containing protein, carb and fat.
  • Eat when hungry – if you have a low appetite, you may need dietary support with help with food combining and digestive enzymes.
  • Don’t eat for a minimum of 3 hours before bed.
  • Aim for an overnight fast that last 12 hours – eg 7pm – 7am.

Do you feel that you need support with diet, weight loss and energy?

Book a call and find out how we can help…

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