Your gut feeling : A brief introduction to gut microbiota of the elders by Fauzan Ahmad.

The ageing process is multifactorial and complex, that bring impact on the human body entirely [1]. The process seriously affects the human gut microbiota in particular, because it is accompanied by changes in the physiology of the gastrointestinal tract and associated immune system [2-4] due to reducing physical-activity levels and daily food intake (especially protein) with respect to lifestyle changing [5, 6]. In the elderly, the diversity and composition of the microbiota has been linked with various health parameters - may also be a risk [4] or protective factor in relation to immunoallergic and metabolic disorders [7].

Even though the process of aging is irreducible, the present knowledge believed that the age-dependent muscle loss can be partially diminished with an increased intake of dietary protein [8-10], and is optimally counteracted when adequate protein intake is combined with resistance training [11]. Moreover, the changing composition of the human microbiota is associated with changes in human behaviours [12]. However, this raises several questions about the usefulness of the present knowledge, especially with regard to protein intake and exercise as strategies in defining the composition and diversity of gut microbiota among the elderly.

Progress has been acceler­ated by metagenomics, which combines high-throughput DNA sequencing [13] and computational methods [14] to define the com­position of complex microbial communities without needing to culture the constituents. Most studies of the human microbiota describe bacterial diversity, which typically dominates the cellular fraction of the microbiota; but other taxa, including Archaea, fungi, and other microbial eukaryotes, and viruses can be present [15]. The understanding of the impact of exercise and the nutritional value of foods in terms of relevance to our microbiota is essential in developing new ways to manipulate the beneficial properties of our microbiota by finding ways to integrate health-promoting properties into modern living should be the goal.

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