The Australian almonds are your key to a healthier gut microbiome, writes Kavita Devgan

Regardless of whether you're a professional athlete or simply interested in health and fitness, it's easy to integrate almonds into your routine. In fact, a regular 30-gram handful of Australian almonds contribute to heart health.

The Gut Benefits of ALMONDS

Interest in gut health has increased exponentially over recent years. Understanding what drives a healthy gut is still in its infancy, but current knowledge suggests a healthy gut is dependent on an abundant and diverse gut microbiota. Lower gut microbiota diversity is associated with a range of disorders and disease states, including cardiovascular disease, type 2 diabetes and inflammatory bowel disease. The nutrients that we get from food, in particular fibre,  phytochemicals (particularly flavonoids and polyphenols) and unsaturated fatty acids, can positively impact the gut micro biota. Almonds contain a unique nutrient package that includes all three, but what exactly is the evidence base for nuts and gut health?

Key insights you need to know:

• Gut health, and specifically micro biota balance and diversity, can influence overall health.
• Almonds are one of the few foods to contain a unique package of fibre, phytochemicals and unsaturated fat, that can all positively affect the gut microbiota composition.
• There is established evidence that eating at least 1 large handful (>42g) of almonds daily has a positive effect on gut microbiota- both increasing beneficial bacteria and decreasing potentially pathogenic types.
• Evidence suggests that long-term nut consumption may also decrease the risk of colorectal (and colon) cancer recurrence and death, and this link may be more apparent in women than men. Almonds contain the highest content of fibre, and one of the highest amounts of phytochemicals, of all nuts.

About the research

A literature review investigating the relationship between nuts, specifically almonds, and gut health was conducted by Nutrition Research Australia (NRAUS). A review of the literature was undertaken via the PUBMED database. Study types were limited to randomised controlled trials (RCTs), cohort studies and systematic literature reviews (SLR). Targeted searches were also conducted in Google Scholar using key terms.

Research findings in a snapshot: THE GUT MICROBIOTA

A 2020 SLR and meta-analysis of nine RCTs found strong evidence that both almonds (5 studies) and walnuts (3 studies) can improve the gut microbiota. There was an absence of evidence for other nut types (8). Almonds had a dual effect, increasing the abundance of healthy short chain fatty acids producing bacteria, and decreasing potentially pathogenic bacteria.

In one study, even greater effects were found in children, where 42.5g and 85g of almonds per day over 3 weeks had a more pronounced effect on gut microbiota in four-year-old children compared with their parents.

Is the level of processing important?

Research has shown that whole and chopped almonds have a greater positive impact on the gut microbiota than almonds in butter form. This may be because approximately 50% of the fibre content of almonds is found in the almond skin.

How are Almonds linked to GUT HEALTH?

Nuts are one of the few foods that provide a nutrient package of fibre, phytochemicals (flavonoids, flavanones and polyphenols) and unsaturated fatty acids, which may explain their strong beneficial effects on bacterial abundance and microbiota composition.

Fibre is well known to provide important fuel for colonic bacteria, and phytochemicals act like prebiotics, positively influencing the maintenance of healthy and diverse microbiota. Unsaturated fatty acids have been shown to have antimicrobial properties and also benefit gut microbiota composition.

Amounts and frequency

• One large handful (42g) of almonds or walnuts per day over 3-12 weeks had positive effects on the gut microbiota.
• Two or more handfuls (57g) of nuts per week were associated with a lower incidence of colorectal cancer recurrence and death.

The author is the Simone nutrition program ambassador of Australian Almonds.