Are you confused about which supplements are science-backed and worth your time? Dr. Megan Rossi, founder of The Gut Health Doctor, is here to cut through the noise.
While it’s exciting to see the growing awareness of gut health, it’s also frustrating to watch companies hop on the trend with misleading products that lack scientific backing. The truth is, feeling and looking your best doesn’t need to be complicated or expensive.
For most people, optimal gut health cannot be achieved with supplements alone, but instead requires a plant-rich, diverse diet that acts as a natural fertilizer for your “good” gut bacteria, helping them thrive.
Probiotics
There is strong evidence to support a number of condition-specific probiotics that can help manage specific symptoms or conditions. However, here is the thing: You need to take the right strain (i.e., type of bacteria), at the right time (e.g., if you need to go on antibiotics), and you need to take it in the right way (i.e., for the right length of time and dose).
For example, research has shown that if you need to take antibiotics, then taking the probiotic Lactobacillus rhamnosus GG throughout and for a week afterward significantly reduces your risk of antibiotic-associated diarrhea, which affects as many as one-third of patients. There are also several other evidence-backed probiotics available for female health, infant colic, and cold and flu, to name a few. To learn more about the science of probiotics, you can join my free probiotic webinar.
Psyllium husk
For those struggling with bowel irregularities, psyllium husk is a simple, evidence-based supplement that can help manage both constipation and diarrhea. Research, including studies from King’s College London, shows psyllium is unique because gut bacteria don’t digest it like most fibers. Instead, it absorbs water, helping soften hard stools or thicken loose ones. Psyllium can also alleviate other symptoms, like incomplete evacuation — the feeling that your bowels aren’t fully emptied. Start with half a tablespoon (around 3g) daily, and gradually increase to a maximum of 3 tablespoons per day, ensuring you add an extra 150ml of water per tablespoon to support psyllium’s role.
Vitamin D
Vitamin D is another supplement worth considering not just for your immune health (as commonly advertised) but your gut health, too — particularly during the darker months. In places like the United States, United Kingdom, and Canada, limited sunlight in the autumn and winter makes it challenging to maintain adequate levels. Vitamin D3 (cholecalciferol) is the most effective form for raising your levels according to a review of 20 studies (compared to vitamin D2, often found in plant foods like mushrooms). Also, vitamin D is fat-soluble, meaning it’s best taken with a meal that includes healthy fats to aid absorption. Think oily fish (like salmon or mackerel), extra virgin olive oil, avocado, nuts, seeds, or full-fat yogurt.
As a general rule, aim to meet your nutritional needs through a diverse, plant-rich diet (think 30 plant points per week), fermented foods, and oily fish before turning to supplements. If you have specific health concerns or suspect you might need supplementation, consult a healthcare professional or registered dietitian who can provide personalized, science-backed advice tailored to your needs.
