Old Age and Probiotics
Life expectancy has increased substantially over the last few decades. Unfortunately, good health in later years has not increased with it. Instead, there’s a longer period of time in which health is deteriorating and functional impairment is increasing. Age-related chronic diseases begin to emerge, such as heart disease, cancer, arthritis, diabetes and Alzheimer’s disease.
The fastest growing population group is people aged 85 years and older. Finding ways and means to help the aging retain good health until later in life is imperative. The medical establishment recognizes that there is a need for better understanding of the interaction between the body, the external environment, and the inner microbial environment of the intestines.
The intestinal microflora have essential roles in health: the breakdown and metabolizing of nutrients (especially fats and fiber), the production of vitamins, and bolstering of the immune system. Probiotics are known to be helpful in normalizing intestinal flora in younger people, raising interest in discerning whether the elderly can derive the same benefits.
Microflora Changes in Old Age
The intestinal lining is one of the body’s main defenses against pathogens (disease-causing elements), along with its function of absorbing water and nutrients from the diet. It’s well established that probiotic intervention is a useful tool in maintaining the health of the gastrointestinal (GI) tract. The composition of the microflora changes with age. Elderly people have a different composition of microflora than do younger people, making it important to define the strains of probiotics which are most effective and well-tolerated by the elderly.
Malnutrition is known to be common in the elderly – about 7% of seniors living at home are malnourished; that figure doubles in people of old age (80 and older). It disturbs the gut microflora. Being homebound and ill are risk factors for malnutrition in the elderly.
Lactose intolerance increases with aging. Fermented milk products, primarily yogurt, seem to be better tolerated than non-fermented products. So-called “bio-yogurts” usually contain L. acidophilus and B. bifidum, which are stable in the presence of bile, and therefore don’t metabolize sufficiently to produce the enzyme which helps in tolerating lactose. Another probiotic in common use in bio-yogurts is L. rhamnosus, which does not metabolize lactose. These probiotics, in bio-yogurts, are not as well-tolerated as ordinary yogurt with live cultures.
One of the changes of intestinal microflora that occurs with aging is a significant drop in numbers of Bifidobacteria. It isn’t clear whether the drop-off is a cause, or an effect of constipation, which is very common in the elderly. It is known that changes in intestinal microflora can alter bowel motility, and that the short chain fatty acids produced in the bowel, have an important impact on transit time. It is postulated that a logical approach to managing constipation in the elderly would be to add Bifidobacteria to the diet. Research is needed.
There is a high rate of diarrhea with antibiotics used in old age, due to overgrowth of Clostridium difficile. Elderly patients in the hospital are more susceptible than other patient groups. Research on the effectiveness of probiotics in these circumstances is needed.
The ability of the body to mount an effective defense against infection occurs in the elderly, a phenomenon called immunosenescence. Various probiotics, such as L. casei and B. lactis, have immune-stimulating effects. Their use in the elderly as immune system boosters is under investigation.
Conclusion: Old Age and Probiotics
These three problems: malnutrition, constipation, and decline in immune function, all common in the elderly, may benefit from probiotic therapy. Further work is necessary to determine long-term effects, and which particular strains are effective and safe.
If you’re looking for a basic background explanation, you’re invited to read this article: What are Probiotics?
Old Age and Probiotics: Research References
- Cusak S, Claesson MJ. How beneficial is the use of probiotic supplements for the aging gut. Aging Health 2011; 7(2):179-186
- Hamilton-Miller JM. Probiotics and prebiotics in the elderly. Post Grad Med J. 2004; 80:447-451