Nuts and seeds feature in our Best Ever Poop Plan as a great source of fibre. They typically contain a mix of both insoluble and soluble fibre with some decent low-FODMAP serving sizes. But with these nutrient powerhouses it’s a case of come for the fibre, and stick around for a whole load of extra beneficial nutrients you get for free. In particular, they are fabulous sources of antioxidants that can help with healthy ageing.

In this blog, we’re focusing in on nuts. We’ll take you through the low FODMAP serving sizes of tasty nuts, outline some of the health benefits and link through to the recipes for some of our favourite ways to enjoy them.

*Peanuts are actually legumes not nuts.

So now is probably a good time for a quick bit of botany and a definition of nuts. A nut is actually a type of fruit – typically dry with a high oil content. The whole fruit consists of a hard or tough nutshell protecting a kernel, the edible bit we eat. In botany, the term "nut" implies that the shell does not open to release the seed. That means that almonds, pistachios and Brazil nuts are not also not nuts in a botanical sense. To keep things simple, we are going to use ‘nuts’ in the culinary sense and include everything except coconuts here.

Minerals

Nuts are rich sources of copper and magnesium, important for heart health. Pine nuts and almonds are the richest in magnesium. Whilst, pine nuts, pistachios are the best nuts for copper. Nuts are also fairly good sources of potassium - the best being pistachios and almonds. Most nuts have a good amount of iron and zinc, but all are fairly low in calcium.

For a good dose of heart-friendly minerals, try adding pine nuts to salads and pasta sauces like this Crispy Prosciutto Pasta.

Plant Phenols

There is growing evidence to suggest that the wide-variety of phenolic compounds found in nuts have cardioprotective, anti-inflammatory, anti-oxidative and neuroprotective effects. Some these effects are derived via metabolites produced by the microbiome as the bacteria feed on the plant phenols. Whilst all nuts have high levels of phenolic acids and flavonoids, the type varies across different nuts. Walnuts for example are rich in vanillic acid, catechin, pyrocatechin, protocatechuic acid, epicatechin, syringic acid, gallic acid, juglone and cinnamic acid, ellagic acid, rutin - quite a list.

Zooming in on the neuroprotective effects, it is interesting to note that traditional Persian medicine has long employed almonds, hazlenuts and walnuts to improve brain health and memory. Animal studies have indicated that these nuts may be helpful in preventing Alzheimers disease and even indicated the specific compounds that may be important.

However. it is likley that rather than a single chemical being responsible for the brain health enhancing effects, there is a synergistic effect from the antioxidant effects of the vitamins and phenols, plus the fibre, minerals and omega 3 fatty acids acting to reduce high cholesterol and blood pressure that can contribute to dementia.

Written by: Dr Mary Webberley, Chief Scientific Officer at Noisy Guts. Mary has a background in biology, with two degrees from the University of Cambridge and post-doctoral research experience. She spent several years undertaking research into the diagnosis of IBS and IBD. She was the winner of the 2018 CSIRO Breakout Female Scientist Award.