Why Do I Crave Sugar? The Science You Need to Know

If you’ve ever opened the fridge at 10 p.m. looking for that sweet treat, you’ve probably asked yourself, maybe even out loud, " Why do I crave sugar? ” And because it’s a common side effect of digestive and hormonal dysfunction (more on that later), it’s a question I regularly get asked by clients. I remember it all too well when I was struggling with gut health issues and an incessant need to eat another brownie. As always, I’ve left the old wives tales and myths about sugar behind to focus on the latest science so you know exactly what’s going on in your body and why sugar cravings are driving you crazy.

Is sugar really addictive?

The first thing to get straight is that craving sugar isn’t all about a lack of willpower. No, the truth is that sugar can be addictive. In fact, the science on this is pretty clear: eating sugar causes the brain to release opioids and dopamine, which are neurotransmitters most often associated with the rewarding effects of drug abuse.

Some researchers have even found that in controlled rat studies sugar is more addictive than cocaine. And while it might be a little premature to label them ‘cocaine cookies’, it’s definitely time to accept that sugar cravings and addiction is a real thing… And yes, that means withdrawals are also very real.


Side effects of sugar?

In many ways, sugar is the new fat. Where fat was (wrongly) vilified in the 20th century, sugar has well and truly (rightly) taken its place in the 21st. And it’s not hard to see why. Everything from obesity and diabetes to cardiovascular disease and cancer has been linked with excess sugar consumption. And for those with digestive issues, there are two key reasons why you should be worried about the white stuff.
1. Sugar suppresses the immune system - there’s evidence to suggest that sugar can decrease immunity and if you have a compromised digestive system already, that’s the last thing you need.
2. Sugar promotes inflammation – given that low-grade inflammation is the source of many chronic diseases, sugar’s inflammatory response is really concerning for those already suffering with chronic health conditions and autoimmune disease.

Now that we know the not-so-sweet truth about sugar addiction and how it is ruining our health, let’s find out the answer to our burning question, why do I crave sugar?

Why Do I Crave Sugar? What the Science says...

Cravings are a signal that a system of the body is out of balance. Which means that cravings are not always a bad thing. When you are dehydrated, you crave water. When you are tired, you crave sleep. These are clever ways your body communicates what it needs.

So why do I crave sugar? Surely that’s not a good thing? Well, here’s a few reasons your body might be craving something sweet:

1. Sugar and artificial sweeteners

What? Eating sugar causes sugar cravings? Yep, that’s basically how an addiction works. This is the most obvious one so we’ll keep it short and sweet. As mentioned earlier, the brain releases opioids and dopamine after eating sugar - ‘happy’ chemicals that keep you coming back for more. It’s a vicious cycle and as with any drug, it’s hard to break. And new research suggests artificial sweeteners might be even worse. Just another reason to put down the Splenda.

It’s daunting and a little ‘tough-love’ but the best solution to cut sugar cravings is to go cold turkey and be ready to deal with withdrawal symptoms. But, the good news is that within two weeks of cutting out all added sugars and artificial sweeteners, the hold has already started to break and the appeal of sweet food has generally reduced significantly. There are lots of awesome online resources and books to help with quitting sugar, like the I Quit Sugar book by Sarah Wilson.

2. Hypothyroidism

Hypothyroidism occurs when the thyroid gland is unable to produce enough thyroid hormone for your body. The thing is, researchers have long known that hypothyroidism can also lead to hypoglycaemia. That is; low thyroid, low blood sugar. So by craving sugar your body is simply trying to balance blood sugar levels. If you also struggle with sensitivity to the cold, constipation, coarse hair, dry skin, have unexplained weight gain or fatigue, then an underactive thyroid could be to blame.

The best thing to do is get your thyroid hormone levels checked using a comprehensive test, and make sure your practitioner uses functional lab ranges to know if they’re out of balance. If you have hypothyroid symptoms, the markers you want to have tested are: TSH, Total T4, Total T3, Free T4, Free T3, Reverse T3, T3U, Free T4 Index and TPO and Anti-TG Antibodies (Hashimoto’s screener).

3. Stress

Many of us have first hand experience with this… a block of chocolate after a difficult day anyone? Researchers have even studied this very thing and found that, and I quote: “Stressed women are more prone to sweet cravings.” This study specifically highlights the role of cortisol, our stress hormone, in hunger and a preference for sweet foods.

Stress management is a massive area, and very much influenced by lifestyle changes. It can be hard to prioritise, but if you think of it this way - stress causes a rise in our stress hormone, cortisol, which induces sugar cravings, which leads to an increase in body fat - then I hope you can see why it should be a priority. Manage stress by using meditation (Headspace App is a great place to start), breathing, journaling, reading, watching a funny movie, or listening to music you love. Relaxation time in the evenings helps to switch the brain off and lower our stress hormone, cortisol. This means we are becoming sleepy and ready for bed, rather than tired, wired and ready for hot chocolate and cake.

4. Lack of sleep

Basically, a bad night’s sleep makes it more likely you’ll reach for a sweet, sweet donut. This recent study found that in adolescents, sweet foods became more appealing when sleep was restricted, backing up previous research on the topic. It’s all about impaired glucose metabolism and increased insulin, which reduces blood sugar levels and kicks off the craving for sugar. Because partial sleep deprivation also affects the appetite-regulating hormones, leptin and ghrelin, not only are you craving sweet foods, you’re craving A LOT of them.

The solution is very simple, to get sufficient quality sleep. Start by working towards 7-9 hours of sleep each night, with your head hitting the pillow by around 10pm. The hour before you head to bed should ideally be technology free to avoid blue light exposure stimulating cortisol (our stress hormone mentioned above) production. If you need to use technology, there are Apps and tools you can download to reduce blue light exposure, like F.lux for laptops and computers and the Night Shift setting available on the iPhone.

5. Mineral deficiencies

A number of minerals are involved in regulating blood sugar levels and, indirectly, sugar cravings. The three minerals that get the most attention when it comes to sugar cravings are magnesium, chromium and zinc. While most of the evidence for a direct link between mineral deficiencies and sugar cravings are anecdotal, their role in blood sugar regulation is fairly settled. The most common of these that I see in clinical practice is magnesium deficiency, which we support using magnesium supplementation.

We also get minerals from the food we eat. But sadly, a diet low in fresh fruit and veggies, as well as the impact of over-farming the soil, means we are more likely to be deficient in essential minerals and craving sugar as a result. The easiest fix, beyond eating more plants, is to take a multimineral supplement to help boost our overall mineral levels in the short term. I like to use Vital Earth, Fulvic Humic Minerals. Start with 15ml with your dinner each night and build to the full recommended dose if tolerated.

6. Candida

Our gut microbiome plays an important role in the way we digest food, synthesise vitamins and fight-off gut infections, amongst countless other functions. It is also thought that our gut microbes can affect host (that’s us) eating behaviour in a way that promotes their health at the expense of ours. The best example of this is Candida and sugar cravings.

Candida is a type of yeast commonly found in our digestive tract, without causing us any issue. But when our immune system is compromised or our gut bacteria is out of balance, this opportunistic yeast species can overgrow and causes problems. And because Candida’s primary fuel source is sugar, it’s no surprise that this is what it craves. This study described a symptom of Candida perfectly as a “ravenous appetite for sweets”. One hypothesis is that the yeast consumes all the sugar and leaves nothing for us, causing our blood sugar levels to drop and our sweet craving to kick in.

If you know you have Candida and can’t seem to beat it, or you think you might be suffering from an overgrowth, then the best thing to do is get tested for it and other gut infections. Because Candida is opportunistic, there may be other gut infections, such as SIBO, parasites or bacteria that are fuelling your Candida overgrowth and causing you to crave their favourite fuel source - sugar. All of these infections need to be treated before you can feel great again, so please get in touch if you would like guidance with this process. HERE is a link to learn more about how we work and why it might be different to what you have tried before.

How to find out the reason you crave sugar

I’m really hopeful that the science in this post has helped you get the answer to; why do I crave sugar? And that you now know it’s very likely not a willpower issue, but something more real. A signal coming from your body telling you that something is out of balance.

Your mission, should you choose to accept, is to start making changes to your diet (e.g. cutting out excess sugar and increasing intake of vital nutrients) and lifestyle (e.g. sleep and stress management). And if this isn’t enough, then it is time for you to get tested. Whether it’s hormones, mineral deficiencies or a gut infection, finding the root cause is half the battle in solving the problem.

Go forth and kick that sugar craving to the curb. You don’t need to carry it around anymore.