As a result of our advances in medical technology we are now able to diagnose and treat more health conditions than ever. Subsequently we are living longer, and the focus has turned to ‘health span’- ensuring the later years of our lives remain comfortable(1). One aspect of this revolves around analysing the changes within our gut microbiomes and how they are linked to debilitating issues often experienced with age. As we age our levels of friendly bacteria are known to fall, particularly in individuals aged 55 onwards(2). Moreover, with age our immune systems deteriorate (a process known as immunosenescence) which can contribute to the negative changes to the microbiome(3). The resultant imbalance in beneficial and pathogenic bacteria (gut dysbiosis) is believed to contribute to the increased sensitivity to stomach and intestinal issues often experienced with increased age2. Some of these health conditions include bloating, diarrhoea, constipation and IBS; all of which stem from gut issues(3). Several studies have looked at providing older individuals with probiotic bacteria supplements as a means to improve their gut microbiome diversity in order to potentially treat these common health conditions. A Japanese survey of 20,000 middle aged and elderly consumers compared those who drank a probiotic milk containing a Bifidobacterium longum BB536 strain against to those who drank normal milk(4). The study’s results suggested individuals who had the daily probiotic drink reported improved immune function, less frequent constipation and less fatigue than the normal milk drinkers as well as improvements in quality of life. Despite these promising results this research was conducted as a survey rather than a clinical trial. A fully controlled clinical trial would be required to understand the benefits of this strain.
This kind of scientific study was carried out by the University of Reading. In this trial two groups of healthy elderly volunteers received either a daily probiotic supplement of Bifidobacterium lactis Bi-07 or a maltodextrin placebo for three weeks(5). Blood, faecal and saliva samples were taken to analyse microbiome composition and immune function. Fascinating results suggested that those who received the probiotic had improved
immune function, due to a significant increase in the phagocytic activity of white blood cells (monocytes and granulocytes). This increase in phagocytic activity following probiotic supplementation has been reported in several other studies(6).
The action of phagocytosis (engulfing bacteria or infected cells) is one mechanism through which the body prevents infection. As a result, this research suggests benefit for older people in supplementing with probiotics to improve ‘healthspan’ at least in the short term. Long term studies would need to be done to decide if there are long tasting effects on the immune system.
Figure 1. The process of phagocytosis.
Olshansky. S.J. From Lifespan to Healthspan. 2018 Oct 2;320(13):1323-1324
Ouwehand AC. et al.Influence of a combination of L. acidophilus NCFM® and lactitol on healthy elderly: intestinal and immune parameters. J Nutr. 2009.; 101(3):367-75.
Kumar, M. et al. Human gut microbiota and healthy aging: Recent developments and future prospective'. Nutr Healthy Ageing; 2016. 4(1): 3-16
Lehtinen M, Maneerat S, Childs C. Consumption of Bifidobacterium lactis Bi-07 by healthy elderly adults ehnances phagocytic activity of monocytes and granulocytes. Journal of Nutritional Science, Vol 2
Gill H.S. Enhancement of immunity in the elderly by dietary supplementation with the probiotic Bifidobacterium lactis HN019. Am J Clin Nutr, 2001.74(6):833-9.
Miller L.E. Short- term probiotic supplementation enhances cellular immune function in healthy elderly: systematic review and meta-analysis of controlled studies. Nutr Res. 2019