ZOE study: Fermented food improves mood, energy, and hunger

If you’ve followed ZOE for any length of time, you’ll know that we’re fans of fermented foods.

Containing live microbes and the complex suite of compounds that they produce, fermented foods have been shown to improve your gut microbiome.

We presented our findings at the annual American Society of Nutrition conference held in Orlando, Florida. 

Here, we’ll briefly outline what we did and what we found. Spoiler alert: You should consider adding more fermented foods to your shopping basket. 

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Thousands of extra servings

In total, 6,493 participants aged 18–80 logged any fermented foods they ate for 3 weeks. For the first week, they followed their normal diet. 

Then, for the final 2 weeks, we asked them to increase their intake by three portions per day.

So, those who didn’t normally eat any fermented foods would aim for three portions per day, and someone who normally ate three portions each day would aim for six, and so on.

Each day, participants filled out a questionnaire in an app that asked them to rate their bloating, mood, hunger, and energy on a 10-point scale.

Were there any benefits?

Next, the scientists compared participants’ questionnaire responses on day 1 with their responses from day 21. Their analysis found that the increase in fermented food was associated with benefits:

• 47% reported improved mood

• 56% reported improved energy

• 52% reported reduced hunger

• 42% reported less bloating

Interestingly, when ZOE’s scientists analyzed people living with obesity, they found that they had even greater improvements in hunger, energy, and bloating than people who were not living with obesity.

Any downsides?

As with most dietary changes, people tended to respond differently, and not everyone experienced benefits. Some reported no change, and others reported worse outcomes. For instance:

• 24% reported poorer mood

• 20% reported less energy

• 25% reported increased hunger

• 25% reported increased bloating

The take-home message

All in all, upping fermented food intake by an extra three portions per day seems to improve mood, energy, bloating, and hunger for the majority. In particular, those living with obesity appear to benefit most.

If you’d like to learn more about fermented foods, we have an article on fermented foods and their benefits and a podcast on fermented foods and gut health. 

And if you’re feeling adventurous, why not try this beginner’s guide to fermenting at home — it’s easier than you might think!