20: Is Fibre the new protein?

Measure. Understand. Improve.

QUICK TAKES

Takeaways from content we’ve enjoyed & other timely topics

Nutrition's Unsung Hero Is Having a Moment

With protein dominating the nutrition spotlight, fibre is finally getting overdue attention. Fibre does far more than support regularity. It can help lower cholesterol, reduce blood glucose spikes, nourish healthy gut bacteria, moderate appetite, and support long-term colon health.

Unlike most nutrients, fibre passes through the digestive tract largely undigested. Insoluble fibres found in vegetables, nuts, and whole grains help with regularity. Soluble fibres, like psyllium, oats, chia, and legumes, help stabilize blood glucose and cholesterol. Fermentable fibres, including resistant starches and inulin, feed gut bacteria, producing compounds like butyrate. These appear important for gut lining integrity, inflammation regulation, and overall metabolic health.

Fibre plays a role in four main areas. Let's break it down...

1) Weight management: High-fibre meals slow digestion and increase fullness, which can lead to weight loss. A meta-analysis of 62 randomized controlled trials found that viscous fibre added to an unrestricted diet produced a modest average weight loss (about 0.7 lbs), with greater effects seen in overweight individuals and those with diabetes. Effects were larger alongside calorie restriction (about 1.8 lbs of weight loss). In overweight and obese adults, soluble fibre supplementation has been associated with about 5.5 lbs of weight loss over 2–17 weeks, though results vary considerably between studies.

2) Blood glucose control: Consuming viscous fibre before or with a carb-heavy meal can blunt post-meal glucose spikes and reduce insulin demand.. We regularly observe this effect with continuous glucose monitoring. A meta-analysis of randomized controlled trials in people with type 2 diabetes, found that soluble fibre supplementation reduced HbA1c levels by approximately 0.5–0.6%. It is thought that a daily dose of about 7.5–8.5 g of soluble fibre is enough to trigger a glycemic benefit.

3) Cholesterol management: Soluble fibres can lower LDL cholesterol by binding bile acids in the gut, forcing the liver to use circulating cholesterol to make more bile acids. A large meta-analysis of 181 randomized controlled trials found that every 5g/day increase in soluble fibre was associated with a reduction in LDL cholesterol of approximately 0.14 mmol/L. Psyllium at a median dose of about 10 g/day reduced LDL cholesterol by about 0.33 mmol/L.

4) Colorectal cancer prevention: Butyrate produced from fermentable fibre may help protect colon health. Viscous fibres can also bind potentially harmful bile acids. A meta-analysis estimated a 10% reduction in colorectal cancer risk per 10 g/day increase in total dietary fibre. However, this was based on observational studies, so we can’t fully separate fibre from other healthy lifestyle factors. Randomized trials of fibre supplements have not shown a similar reduction in cancer risk. The American Cancer Society recommends consuming fibre from whole plant foods rather than supplements for cancer prevention.

Individuals tolerate fibre differently; more is not always better. For example, those with irritable bowel syndrome or FODMAP intolerance (difficulty digesting certain types of carbs) may experience gas, bloating, and abdominal discomfort from foods like beans, onions, and apples. These individuals may tolerate psyllium or resistant starches from cooled rice or potatoes more easily. Increasing fibre gradually and staying well hydrated can improve tolerance.

Note that viscous fibres can delay the absorption of certain medications, so it's important to consult your doctor about timing if you take fibre supplements alongside prescription drugs.

Current recommendations put adequate intake at 25 g/day for women and 38 g/day for men, though most people consume far less. A major Lancet review found that the greatest health benefits were seen at intakes of at least 25–29 g per day, with data suggesting additional benefits at higher intakes.

Here are some simple strategies to increase fibre intake:

Add chia or flax to yogurt or oatmeal
Include beans or lentils a few times per week
Eat berries, apples, pears, and avocado more regularly
Snack on nuts and seeds or add to salads
Try overnight oats or cooled potatoes/rice for resistant starch

Different plants feed different gut bacteria, so variety is important. A good target is to eat30+ plant varieties a week. Fibre consumption may be one of nutrition’s simplest high-reward habits.

COMMUNITY BUZZ

Highlights from Benchmark’s community

Entering our Fibre Era 🍎

Move over protein, fibre is fast becoming the food industry's nutrient du jour. Olipop and Poppi created the “prebiotic soda” category. Coca Cola followed suit with Simply Pop, while Pepsi acquired Poppi and launched its own Pepsi Prebiotic Cola. New fibre supplements have emerged, replacing back-of-the-cabinet "digestive aids" like Metamucil into Gen-Z-approved brands like BelliWelli that offers fibre gummies with electrolytes, collagen, and probiotics. Expect to see fibre-infused products and fibre-forward positioning pop up more as marketers catch on (read the labels!).

Members are sharing their high-fibre picks, including Carbonaut bread, with higher fibre content, more protein, and fewer carbs than most bread. Its gluten free white bread has 16 grams of fibre. Another member told us she eats the whole kiwi (skin and all) to get even more fibre and antioxidants. And, in this month's Office Hours, we shared a high-fibre snack to curb afternoon carb cravings: mix 2T chia seeds, 1T ground flaxseed, hot water, and a dash of cinnamon. 👌

A "Fitbit for Farts"? 🙊

This seems like the right time to share what several members have passed along to us recently. You too may have seen headlines for the "fitbit for farts." Developed out of the University of Maryland, it is "the first wearable device to measure human flatulence." To establish population benchmarks, the lab is recruiting study participants to build the "Human Flatus Atlas". 👀 All jokes aside, this could be a powerful tool. The device continuously tracks hydrogen in the wearer's "flatus." Because hydrogen is produced exclusively by gut microbes, this offers insight into when, and how actively, fermentation is occurring in the gut microbiome. This could help us understand individuals' variable responses to dietary fibre, and the gut's microbial fermentation process.

A Breath of Fresh Air 💨

And on that note...a friend recommended this CO2 monitor that he uses to track indoor air quality. It's easy to overlook air quality until wildfire season rolls around, but it impacts our health everyday. Air quality indoors, where we spend 90% of our time, is typically far worse than outdoors. One of the simplest things we can do to improve it? Open the windows, even for just a few minutes a day. Better ventilation lowers CO2 and airborne pollutants like VOCs, which can meaningfully impact cognitive performance and health. A meta-analysis found that adequate indoor ventilation improved task performance speed by about 14% and reduced arithmetic errors by about 16%. Not bad for simply opening a window.