Beans, whole grains and nuts – the secret to longer life

Added on
17 Mar 2022
Beans, whole grains and nuts – the secret to longer life


The team from Norway undertook a modelling study using meta-analysis and databases from the established Global Burden of Disease 2019 dataset which associates various dietary components with mortality mainly as a result of cardiovascular disease (CVD), diabetes and cancer.

The method

Using these datasets, the team investigated the impact on life expectancy if individuals were to shift from ‘Typical Western’ (TW) eating habits to:

  • An optimised sustainable diet (OD) such as that recommended by EAT Lancet diet and daily food quantities set at levels beyond which no further benefits would be gained OR
  • A feasible approach (FA) option: half-way shift between current eating habits and the optimised diet

Table 1: Details of specific foods and their daily recommended quantities included in the analysis for the three dietary scenarios

Whole grains50 g137.5 g225 ge.g., 2 thin slices of rye bread and 1 small bowl of whole grain cereal  and some whole grain rice). For whole grains  225 g of fresh weight corresponds to about 75 g dry weight equivalent of 7 servings/day);
Vegetables250 g325 g400 g5 servings e.g., 1 big tomato  1 sweet pepper  mixed salad leaves a half avocado  and a small bowl of vegetable soup);
Fruits200 g300 g400 g5 servings e.g.  1 apple  banana  orange kiwi  and a handful of berries);
Nuts0 g12.5 g25 g1 handful of nuts
Legumes0 g100 g200 ge.g., 1 big cup of soaked beans/lentils/peas
Fish50 g125 g200 ge.g., 1 big slice of herring
Eggs50 g37.5 g25 gHalf an egg
Milk/dairy300 g250 g200 ge.g., 1 cup of yoghurt
Refined grains150 g100 g50 ge.g., refined grains in bread if mixed whole/refined bread
Red meat100 g50 g0 g
Processed meat50 g25 g0 g
White meat75 g62.5 g50 g
Sugar-sweetened beverages500 g250 g0 g
Added plant oils25 g25 g25 g

TW = Typical Western Diet – a combination of US, China and European databases

FA = Feasibility Approach: halfway between TW and optimised diet

OD = optimized diet – e.g., EAT Lancet with food quantities set at levels beyond which no further health benefit could be gained (according to meta-analysis data)

The results

Prolonged life years could be gained by a sustained change to either the OD or the FA.  The latter providing (on average) half the expected gains compared to the OD but still significantly improving life expectancy compared to continuing on the current TW diet.

The full impact results are achieved after the improved dietary habits are adopted for a period of 10 years.  However, based on meta-analysis data, increases to life expectancy would start from 2 years of adoption and gradually increase year by year to plateau at 10-years.

Improved life expectancy across all age ranges

Starting young would result in the biggest benefits.  A 20-year-old male shifting to OD pattern would expect to increase life expectancy by 13 years and a woman by 10 years, whilst shifting to OD at 60 years would result in an 8.8-year and 8-year gain for men and women respectively. Even making the shift at 80 years could prolong life by 3.4 years for men and women.

More beans, nuts and whole grains and less red and processed meat hold the key to prolonged life!

When assessing the individual food components for optimum impact on life expectancy, there were some clear winners:

  • Consuming more beans (200g daily), whole grains (5 servings daily) and a handful of nuts daily
  • Avoiding red and processed meat was clear that legumes, whole grains

It’s important to note that even achieving the FA quantities i.e., not avoiding but instead halving current red and processed meat intakes and consuming beans, whole grains and nuts daily but at half the quantities of the OD would still produce significant results.

In summary

Shifting to a plant-based sustainable diet will significantly prolong life expectancy, mainly through improved CVD, diabetes and cancer outcomes.  The earlier in life population groups make the transition the better the outcomes, however, all age groups can benefit and reduce their disease burden by adopting healthier diets now. The fact that even part transition to the optimum diet can produce significant improvements should be used as a motivating factor for those finding the dietary shift a challenge. The optimum diet is clearly far removed from current eating habits, so it may be beneficial to focus on introducing the dietary changes in a step-by-step manner and starting with the foods likely to produce the biggest impact i.e., more beans, whole grains and nuts and reducing red and processed meat.

Fadnes LT, Økland J-M, Haaland ØA, et al. Estimating impact of food choices on life expectancy: A modeling study. PLoS Med 2022;19(2): e1003889. https://doi.org/10.1371/journal.pmed.1003889