Posted 06.19.2019 | by AMRA

Telomeres are repetitive nucleotide sequences at the end of chromosomes that protect coding regions of DNA from deteriorating during cell division. Telomeres shorten not only as we age, but also when we are under stress. Shorter telomeres are linked to an increased incidence of age-related diseases such as cardiovascular disease, and to an increased risk of death. The enzyme telomerase lengthens telomeres through the addition of nucleotide repeats.

Preliminary studies show that meditation can have a protective effect on telomeres, most likely by increasing telomerase activity. Specific types of meditation may be more effective than others in maintaining telomere length. Nuygen et al. [Psychoneuroimmunology] tested whether specific types of meditation practice have a protective effect on telomere length.

The researchers randomly assigned recruits to mindfulness meditation (MM), loving-kindness meditation (LKM), or a wait-list control. Their final sample (excluding dropouts and participants with inadequate DNA samples) consisted of 142 meditation-naive recruits (average age = 49; 70% female; 81% Caucasian). MM and LKM participants attended six, hour-long, group meditation training workshops held once per week. They also received 20-minute audio-recorded guided meditations to assist in daily home practice.

MM training focused on developing open, non-judgmental attention towards breath, bodily sensations, thoughts, and feelings, as well as choiceless awareness. LKM training focused on cultivating warm feelings towards oneself, a loved one, an acquaintance, a difficult person, and all beings.

Two weeks prior to the workshops (and three weeks after) participants donated a blood sample that was used to assess white blood cell (monocyte and lymphocyte) telomere length. Participant moods and extent of meditation practice were assessed by daily diary.

All groups showed a decrease in telomere length over the course of the study. The mean decrease in telomere length was significantly less for LKM (-0.03) than for the control group (-0.08). The MM group decrease (-0.06) was midway between the other two groups, and not significantly different from either.

The average telomere length decrease for all participants combined was equivalent to a loss of 115 DNA base pairs, which is larger than one might expect over a 12-week period. Other studies suggest white blood cell telomeres shorten by an average of 15-50 base pairs per year. Changes in telomere length were unrelated to participants’ moods or home practice.

This study provides evidence that, in a sample of middle-aged adults, only loving-kindness meditation significantly decreased the degree of telomere shortening over time compared to a control group. The positive emotions associated with loving-kindness meditation may have a protective function in reducing cellular aging and maintaining wellness.

Other factors, however, cannot be ruled out. The fact that this effect was unrelated to mood or home meditation practice makes it hard to specify what it is about LKM training that helped.

The study could not rule out changes in the relative proportion of different white blood cell types present in the blood samples over time that could potentially lead to spurious measures of telomere change. The unexpectedly large magnitude of overall telomere shortening over a relatively brief time span also raises the possibility of unknown collection or assay discrepancies between this study and prior studies.

Reference:

Nguyen, K. D., Lin, J., Algoe, S. B., Brantley, M. M., Kim, S. L., Brantley, J., . . . Fredrickson, B. L. (2019). Loving-Kindness meditation slows biological aging in novices: Evidence from a 12-week randomized controlled trial. Psychoneuroendocrinology.

[Link to study]