Why Fiber Supplements Can Help

You’ve heard it to death by now that a diet chronically low in fiber has been linked to higher risks of cardiovascular disease, digestive disorders, and colorectal cancer. 

Fiber feeds your gut microbiome aka the trillions of microbes living in your digestive tract and when those microbes are underfed, they produce fewer of the beneficial compounds that protect our health.

The problem is that modern diets, dominated by ultra-processed foods and refined carbs, leave little room for the diverse plant foods that naturally deliver fiber. Changing that is always the gold standard…but realistically, many people struggle to consistently hit 30 g a day through diet alone.

The Duke University study

Researchers at Duke University wanted to see whether fiber supplements could help fill the gap and whether the type of supplement mattered.

They recruited 28 adults and cycled them through three common, commercially available prebiotic fiber types:

• Inulin
  

• Wheat dextrin
  

• Galactooligosaccharides (GOS)
  
  

Each supplement was taken for one week, starting with a smaller “intro” dose (4.5 g for inulin/dextrin, 1.8 g for GOS) and then doubling the amount for the rest of the week. A one-week break between phases allowed gut microbes to return to baseline before the next fiber type was tested.

Results

For participants eating low-fiber diets, the change in their microbiomes was striking: all three supplement types increased butyrate production, regardless of which one was used.

So, if you’re not meeting your fiber target, adding any well-tolerated soluble fiber supplement can boost beneficial microbial activity. The researchers concluded that, for the purposes of increasing butyrate, the tested supplements were essentially interchangeable with food (noting that real foods bring other benefits beyond fiber of course)

What this means for you

• Aim for diet first: Whole plant foods bring not just fiber, but polyphenols, vitamins, minerals, and other beneficial compounds.
  

• Use supplements strategically: If you consistently fall short on fiber, soluble fiber supplements can help bridge the gap without the bloating and cramping that sometimes come from high-roughage, insoluble fiber sources.
  

• Go slow: Increase your intake gradually, with plenty of water to reduce digestive discomfort.
  

• Think diversity: Over time, aim for a mix of fiber types from food and supplements to feed a broader range of gut microbes.
  
  

In short, your microbiome doesn’t care whether its fuel comes from lentils or from a scoop of soluble fiber powder but it definitely notices when that fuel is missing. And when you give it enough, it pays you back in ways that can protect your gut, your metabolism, and even your long-term disease risk.

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How I Tackled “Food Noise”...

For years, I thought my problem was “willpower.”

I’d be sitting on the sofa watching TV and suddenly feel this magnetic pull toward the kitchen. 

It wasn’t hunger…not even boredom…but a relentless pang that would grow into a shout until I found myself standing in front of the cupboard, staring down a jar of peanut butter like I had a grudge to settle.

This is food noise.

Not just casual daydreaming about dinner, but persistent, intrusive thoughts about food between meals…in some cases thoughts that can derail your day, dominate your focus, and make you feel like you’re fighting an endless mental battle.

The science of food noise

In simple terms, food noise is your brain’s amplified response to food cues. Those cues can be:

• External: adverts, smells, someone eating next to you
  

• Internal: fluctuations in appetite-regulating hormones like ghrelin (hunger hormone) and GLP-1 (satiety hormone)
  

• Learned triggers: specific times of day, locations, or emotional states tied to past eating
  

The tricky part is that our modern environment is engineered to crank up this volume. Supermarkets, fast-food apps, and even “innocent” Instagram posts are all designed to activate your brain’s reward circuitry (especially the dopaminergic pathways) before you’ve even taken a bite.

Some research even suggests that genetics, stress levels, and sleep quality modulate how loudly you experience food noise. And interestingly, GLP-1 agonists (like Ozempic) appear to quiet these signals, hinting that a big part of the obesity epidemic is not just overeating… but overthinking about eating.

My way of turning down the volume

I used to think the only answer was to “just say no.” 

Restriction never worked for me long term because food noise isn’t a character flaw, it’s a neurobiological response amplified by our surroundings. So I stopped trying to mute it entirely and started managing the volume.

Here’s what worked for me (and what science says helps):

1. Front-load your meals with protein +  fiber: Both trigger satiety hormones (GLP-1, PYY, amylin) that dampen appetite signals. For me, this meant adding oats + chia seeds to breakfast or lentils to lunch.
   

2. Create “cue shields”: I rearranged my kitchen so trigger foods aren’t visible. Out of sight = fewer dopamine spikes. Sounds simple, but environmental design is a huge modulator of behaviour.
   

3. Structured snacking: Instead of grazing, I pre-decide my snacks and eat them away from distractions. This turns “mindless eating” into “planned eating,” which reduces spontaneous food noise triggers.
   

4. Delay and distract: If a craving hits, I set a timer for 15 minutes and do something physically engaging… even folding laundry. About 80% of the time, the intensity fades.
   

5. Hydration first: Mild dehydration can mimic hunger signals. A glass of water before eating often revealed I wasn’t actually hungry.
   

6. Sleep as a food-noise dial: Sleep deprivation increases ghrelin and decreases leptin, which is basically turning your food noise up to 11. I guard my 7–8 hours now like it’s gold.
   

7. Mindful indulgence: When I do decide to eat the thing, I eat it slowly, without guilt, and without multitasking. Paradoxically, this reduced how often I wanted it.
   
   

If you struggle with food noise, it’s not because you’re weak but because you’re human, living in a hyper-engineered food environment. You can’t remove every cue, but you can change how you respond to them.

Think of it like tuning a radio: you can’t switch off the world’s food signals, but you can turn them down so they don’t drown out everything else. And when you learn to do that, you reclaim mental real estate for everything else that matters in your life.

An Actual Science-Backed Hack for Hangovers?! 

I’ll start with a confession: I haven’t had a sip of alcohol since 2020, so I can’t say I’ve personally tested this. 

But as a doctor and professional PubMed nerd (pubmed is this large online repository of research), I went down the research rabbit hole and the science checks out.

Hangovers are strange beasts. You don’t need me to tell you they bring headaches, nausea, fatigue, and the sort of existential dread usually reserved for Monday mornings. That’s on top of the well-documented long-term risks of alcohol from liver damage to increased cancer risk…which is a whole separate conversation.

What is surprising is how little formal research there is on hangovers. Out of curiosity, I typed “hangover” into PubMed and found roughly 600 papers… going all the way back to 1945. For perspective, “vitamin D” returns over 100,000 hits. Hangovers have been more studied by brunch menus than by scientists.

The sweat-it-out theory

In 2024, researchers studied over 1,600 university students who’d had at least one hangover in the previous three months. They looked at how much the students drank, how often they exercised, and how bad their hangovers were.

Unsurprisingly, heavier drinkers had more and worse hangovers. But those who did vigorous exercise regularly…not necessarily during a hangover, just as part of their routine…reported fewer hangovers overall, and the ones they did have were milder.

Mechanistically, it makes sense:

• Endorphins: Prolonged, higher-intensity exercise releases endorphins, which act as natural painkillers. That could dull a hangover headache.
  

• Anti-inflammatory effects: Alcohol spikes inflammation, and exercise (especially consistent exercise) dials it down. Studies show even 20 minutes of moderate movement can activate anti-inflammatory immune cells like regulatory T-cells.
  

• Metabolic boost: Exercise may help your body process lingering metabolic byproducts of alcohol more efficiently.
  

Exercise seems to help protect against hangover severity, but being hungover makes exercise feel harder. So you might not smash personal bests when you’re still metabolising last night’s wine.

My takeaway (as a non-drinker)

I can’t give you a first-person testimonial anymore…my last drink was before “social distancing” entered the dictionary…but the physiology makes sense. If you’re someone who still enjoys a glass (or three), investing in regular, higher-intensity exercise could make your mornings-after a lot less grim.

And if you’re reading this with a thumping head right now… maybe go for a brisk walk first, then build towards the more vigorous stuff. Your liver needs a helping hand. 

P/S: My second book This Is Vital Information is out for pre-order now! It covers everything from guts (even dodgy ones), microbiome, poops, women’s health (endometriosis etc), sex, mental health, cancer and more. Click the link below to pre-order now!

P.P.S If you’ve made it this far, enjoy this guide I’ve written to help you through your next doctor’s appointment!

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