Low intake of calcium, folate, nicotinic acid, vitamin E, retinol, β-carotene and high intake of pantothenic acid, biotin and riboflavin are significantly associated with increased genome instability—results from a dietary intake and micronucleus index survey in South Australia

TLDR

The study aimed to assess how dietary intake of micronutrients relates to genome damage in lymphocytes, measured by the micronucleus assay. Researchers recruited 190 healthy adults (mean age 47.8, 46 % male) and conducted a 6‑month randomized trial supplementing β‑carotene, vitamins C and E, and zinc (ACEZn) to evaluate its effect on genome stability. Higher intakes of vitamin E, retinol, folic acid, nicotinic acid, and calcium were linked to 28–49 % lower micronucleus frequency, whereas higher riboflavin, pantothenic acid, and biotin intake increased micronucleus frequency by 36–65 %; mid‑range β‑carotene lowered micronucleus frequency by 18 % but high intake raised it, and ACEZn supplementation reduced the index by 13 %, with calcium mitigating and riboflavin amplifying folate‑deficiency‑induced damage.

Abstract

The aim of this study was to determine the association between dietary intake, determined using a food frequency questionnaire, and genome damage in lymphocytes measured using the micronucleus (MN) assay. The study, performed on 190 healthy individuals (mean age 47.8 years, 46% males), also examined whether a supplementation with β-carotene, vitamins C and E along with zinc (ACEZn), in a randomized trial for 6 months, improves genome stability. Multivariate analysis of baseline data showed that (1) the highest tertile of intake of vitamin E, retinol, folic acid, nicotinic acid (preformed) and calcium is associated with significant reductions in MN frequency, i.e. −28, −31, −33, −46 and −49%, respectively ( P < 0.005) relative to the lowest tertile of intake and (2) the highest tertile of intake of riboflavin, pantothenic acid and biotin was associated with significant increases in MN frequency, i.e. +36% ( P = 0.054), +51% ( P = 0.021), and +65% ( P = 0.001), respectively, relative to the lowest tertile of intake. Mid-tertile β-carotene intake was associated with an 18% reduction in MN frequency ( P = 0.038); however, the highest tertile of intake (>6400 µg/day) resulted in an 18% increment in MN frequency. Supplementation with ACEZn significantly reduced the MN index by 13% ( P = 0.038). The study also showed interactive additive effects such as the protective effect of increased calcium intake (−46%) and the exacerbating effect of riboflavin (+42%) on increased genome damage caused by low folate intake. The results from this study illustrate the strong impact of a wide variety of micronutrients and their interactions on genome health, depending on the level of intake.