The British Dietetic Association defines a plant-based diet as being based on foods derived from plants, and includes vegetables, fruits, nuts, seeds, wholegrains, legumes, with few or no animal products (1).

There is variation in the types of plant-based diets. Plant-based diets differ in the proportion of animal products included in the diet. Flexitarian diets include mostly plants, with occasional consumption of meat, dairy products and eggs. Pescatarian diets include seafood but exclude animal products. Lacto-ovo vegetarian diets include eggs and dairy products but exclude meat and fish. Vegan diets exclude all animal products (2).

One in five (18.3%) people in the UK are currently sixty five years old or older (3). This age group needs to eat a nutrient rich diet which helps to maintain muscle strength. Unplanned weight loss also needs to be avoided. A well planned plant-based diet can supply all the nutrients needed for good health. The benefits of plant-based diets for seniors are as follows:

Reduced likelihood of being overweight or obese

Vegetarians and vegans in the Western world have a lower weight gain during adulthood (4, 5). Obesity is a major cause of illness and death. These findings might be expected to show a decreased risk of obesity related diseases in vegetarians and vegans. Some studies have suggested the use of vegetarian and vegan diets in weight management (6, 7).

Decreased risk of ischaemic heart disease

Total cholesterol is lower in vegetarians than non vegetarians mainly due to a lower LDL (Low Density Lipoprotein Cholesterol) (8, 9). This is likely due to the difference in fat intake. Meat is a source of saturated fatty acids whereas plant foods such as nuts, seeds and vegetables oils are a source of polyunsaturated fatty acids (8).

Risks for ischaemic heart disease (IHD) appear to be lower in non-vegetarians than vegetarians. Data from the EPIC-Oxford study showed that the risk of being hospitalised or death from IHD was 32% lower in vegetarians compared to non-vegetarians (10).

How plant-based foods can reduce cardiometabolic risk:

• Lower energy density of the diet which helps to optimise distribution of body fat and body weight.
• Low in saturates and high in unsaturates which helps with vascular and endothelial function i.e. maintaining blood capillaries.
• High in both soluble and insoluble fibre which is beneficial for regulating blood pressure and reducing inflammation and blood pressure.
• Contains a bioactive micronutrient profile which can have anticarcinogenic, anti-oxidant, anti-inflammatory, and antimicrobial properties (11).
  

Decreased risk of diabetes

The risk of type 2 diabetes is very strongly related to being obese. Tonstad et al (2013) have shown a decreased risk of self reported diabetes in semi vegetarians, lacto-ovo vegetarians and vegans compared to non vegetarians, using data from the Adventist Health Study-2 (12).

Reduced risk of diverticular disease

Diverticular disease is when small pockets/bulges develop in the lining of the large intestine. Symptoms can include stomach pain, constipation, diarrhoea, occasional blood in poo. Data from the EPIC-Oxford Study showed that the risk of diverticular disease was 31% lower in vegetarians compared to meat eaters (13).

Reduced risk of eye cataract

The EPIC-Oxford Study results have also shown that vegetarians (including vegans) had a reduced risk of eye cataracts compared to meat eaters (14).

Well planned plant-based diets are suitable for seniors and there is evidence that they may have some health benefits. More research is needed on the long-term benefits of plant-based diets.

References:

1) https://www.bda.uk.com/uploads/assets/3f9e2928-ca7a-4c1e-95b87c839d2ee8a1/Plant-based-diet-food-fact-sheet.pdf.

2) https://www.alprofoundation.org/files/AF-update-_Cardiometabolic-health_2020.pdf

3)https://www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationestimates /articles/overviewoftheukpopulation/august2019

4) Rosell, M., Appleby, P., Spencer, E., & Key, T. (2006). Weight gain over 5 years in 21,966 meat-eating, fish-eating, vegetarian, and vegan men and women in EPIC-Oxford. International journal of obesity (2005), 30(9), 1389–1396. https://doi.org/10.1038/sj.ijo.0803305

5) Japas, C., Knutsen, S., Dehom, S., Dos Santos, H., & Tonstad, S. (2014). Body mass index gain between ages 20 and 40 years and lifestyle characteristics of men at ages 40–60 years: the Adventist Health Study-2. Obesity research & clinical practice, 8(6), e549-e557

6) Turner-McGrievy, GM, Barnard, ND & Scialli, AR (2007) A two-year randomized weight loss trial comparing a vegan diet to a more moderate low-fat diet. Obesity (Silver Spring). 15, 2276–2281.

7) Mishra, S, Xu, J, Agarwal, U et al. (2013) A multicenter randomized controlled trial of a plant-based nutrition program to reduce body weight and cardiovascular risk in the corporate setting: the GEICO study. Eur J Clin Nutr 67, 718–724. https://doi.org/10.1038/ejcn.2013.92.

8) Turner-McGrievy, G. M., Barnard, N. D., & Scialli, A. R. (2007). A two-year randomized weight loss trial comparing a vegan diet to a more moderate low-fat diet. Obesity, 15 (9), 2276–2281.

9) Bradbury, K., Crowe, F., Appleby, P. et al. Serum concentrations of cholesterol, apolipoprotein A-I and apolipoprotein B in a total of 1694 meat-eaters, fish-eaters, vegetarians and vegans. Eur J Clin Nutr 68, 178–183 (2014). https://doi.org/10.1038/ejcn.2013.248.

10) Francesca L Crowe, Paul N Appleby, Ruth C Travis, Timothy J Key, Risk of hospitalization or death from ischemic heart disease among British vegetarians and nonvegetarians: results from the EPIC-Oxford cohort study, The American Journal of Clinical Nutrition, Volume 97, Issue 3, March 2013, Pages 597–603, https://doi.org/10.3945/ajcn.112.044073.

11) Jenkins, W., Jenkins, A., Jenkins, A. and Brydson, C., 2019. The Portfolio Diet for Cardiovascular Disease Risk Reduction: An Evidence Based Approach to Lower Cholesterol Through Plant Food Consumption. Academic Press.

12) Tonstad, S., Stewart, K., Oda, K., Batech, M., Herring, R. P., & Fraser, G. E. (2013). Vegetarian diets and incidence of diabetes in the Adventist Health Study-2. Nutrition, Metabolism and Cardiovascular Diseases, 23(4), 292-299.

13) Crowe, F. L., Appleby, P. N., Allen, N. E., & Key, T. J. (2011). Diet and risk of diverticular disease in Oxford cohort of European Prospective Investigation into Cancer and Nutrition (EPIC): prospective study of British vegetarians and non-vegetarians. Bmj, 343.

14) Appleby, P. N., Allen, N. E., & Key, T. J. (2011). Diet, vegetarianism, and cataract risk. The American journal of clinical nutrition, 93(5), 1128-1135.