The increased consumption of ultra-processed foods poses a risk to public health. (1) Previous studies demonstrated its impact in terms of increased occurrence of premature mortality and noncommunicable diseases (Non-Communicable Diseases, NCDs), weakening of the immune system, obesity and overweight.
Recent studies have shown how the ultraprocessed foods they are also capable of causing genetic mutations associated with aging. On the other hand, the Mediterranean diet stands out, a probable elixir of youth. Brief scientific review.
Fresh foods vs ultraprocessed foods
Consumption of fresh food it is in continuous decline, on a planetary level. The food supply in recent decades has in fact been oriented towards ultra-processed foods. That is to say long-life products, generally ready for consumption, at affordable prices that are explained by the low value of the raw materials used. It is irresistible on the palate, thanks to the deadly mix of fat and sugar and / or salt that It has been demonstrated cause a real ‘junk food addiction’.
Ultraprocessed foods they are distinguished by a high degree of transformation that is often associated with high levels of energy (calories) made mainly by fats, saturated fats and sugars. In addition to excessive salt / sodium levels. And that’s why junk food is generally classified as HFSS (High in Fats, Sugar and Sodium). In their formulation (recipe) often appear starches, fibers, protein isolates, additives.
Ultraprocessed foods, which ones?
Ultraprocessed foods the more dangerous ones are generally addressed to children and adolescents (68% of the shelf offer in Europe, according to a study of the European Commission of 2019).
It is snack salty (ex. French fries), snacks and sweets with abundant rations of sugar and palm (or coconut) oil, alcohol-free drinks sweetened and / or sweetened.
The most devious products – junk food in disguise – are then the instant preparations (eg. risotto and nuts with palm oil), the ‘rubber meats’and in general many foods ready-to-eat, also in the vegetarian and vegan versions. (2)
Ultraprocessed foods and health
FAO (Food and Agriculture Organisation), in its own 2019 report on ‘ultra-processed foods, diet quality and human health’, he recognized the desirability of classifying foods and beverages on the basis of their level of industrial processing. According to the approach adopted in the NOVA system, of the University of Sao Paulo (Brazil). In line with those developed byInternational Food Information Council (IFIC) and the University of North Carolina (UNC), in the USA (3,4).
Several studies Analyticals employed the NOVA system to assess the incidence of overprocessed foods in the diet of the observed cohorts. And identify its correlations with the onset of some specific pathologies. Among the most relevant:
– influence of high dietary sugar content on blood glucose levels and anthropometric parameters (body mass index), (5)
– increased risk of mortality (+ 62%) in case of frequent consumption of ultra-processed foods (> 4 servings per day), (6)
– increased risk of cardiovascular, cerebrovascular and coronary diseases correlated to a constant increase in the consumption of ultraprocessed food (7)
– greater risk of chronic degenerative diseases associated with energy supplies mainly from ultra-processed foods, (8)
– direct relationship between consumption of ultra-processed foods, cardiovascular diseases and increased premature mortality. (9)
Telomeres, DNA protectors
The telomeres (from the Greek telos, end, and mere, part) are non-coding sequences located at the ends of chromosomes. In association with specialized proteins, they protect DNA by preserving the integrity and stability of the chromosome. Telomeres vary in length between 4 and 25 kb (kilobases, i.e. the number of nucleotides in the gene sequence). As they tend to shorten as they age, they are also rated as marker the biological age of individuals. (10)
Epigenetics shows how telomeres are modified, in the course of life, by lifestyle and genetic factors. Their shortening is accelerated, in particular, by high oxidative stress and excessive inflammation. This is associated with an increase in the probability of developing various diseases such as hypertension, hyperglycemia and obesity. A healthy diet can, on the other hand, help reduce telomere shortening and thus maintain a better state of health (11, 12).
Telomeres, health and nutrition
A very recent study of the University of Navarra, conducted on 886 individuals aged between 57 and 91 years, showed a positive association between high consumption of ultra-processed foods (> 3 meals per day) and the risk of having shorter telomeres, up to double that of the group that ate less of these foods. (13)
The nutrients and micronutrients that have shown a greater ability to retain telomere length are dietary fibers, Omega 3, vitamins (B9, B12, C, D, E and multivitamins) and minerals (copper and phosphorus). Omega-6, alcohol and in some cases short and medium chain fatty acids have instead shown a negative influence on telomere length.
Oxidative stress, inflammation and diet
The heterogeneity of the studies cited in the previous paragraph suggests the opportunity to further research in this area. However, it is noted that their results are in line with other studies which assessed the relationship between the onset of oxidative stress, inflammatory states and diet. (14)
Various epidemiological studies e trial clinicians have indeed analyzed the relationships between the different food groups and the length of telomeres. One of the most relevant indicates how:
– vegetables, fruits, legumes and nuts are sources of polyphenols and unsaturated fatty acids. Whose contributions, together with those of fiber, are associated with a reduction of oxidative stress and inflammation, and a greater length of telomeres,
– processed and ultraprocessed foods rich in sugars and saturated fats, as well as alcohol, are instead associated with an increase in oxidative stress, inflammation and shorter telomeres. (15)
Fig 1. Forest-plot on the positive effect of ultra-processed foods in the risk of telomere shortening, with the appropriate corrections. (Alonso-Pedrero et al., 2020)
Role of the Mediterranean diet in telomere protection
The Mediterranean diet is recognized as one of the best eating habits available, thanks to a variety of valuable health foods such as vegetables, grains, legumes, fruit, extra virgin olive oil, nuts, fish e dairy product.
These foods they are rich in antioxidants and anti-inflammatories, involved in various protective mechanisms, including telomeres. An important role of the Mediterranean diet was also observed in maintaining the activity of telomerase, the enzyme responsible for the re-lengthening of shortened telomeres (16) And more generally in the prevention of various pathologies, from cardiovascular diseases to depression, cognitive dysfunctions and metabolic syndrome, type 2 diabetes, weight gain and nephrolithiasis. (17)
Fig 2. Scheme of the biological mechanisms involved in the length of telomeres and influenced by the diet (Galiè et al., 2019)
Mediterranean diet, an elixir of youth?
A previous study of a cohort conducted on 4676 nurses aged 30-55 had already shown the effectiveness of the Mediterranean diet in preventing telomere shortening, with a favorable impact on health and longevity. (18) Exposure to the numerous nutrients, micronutrients and phytocompounds that characterize the Mediterranean diet positively influences the length of telomeres, thanks also to their remarkable ability to reduce inflammation and oxidative stress.
It is still not clear if the protective effect on telomeres is due to a specific constituent of the diet, or if it derives from a combination of several elements. (19) The various studies considered in this analysis, however, converge on the positive correlations between the Mediterranean diet – purified from ultra-processed foods that are completely foreign to it – and the protection of telomeres, the integrity of which represents an indicator of biological youth and good health.
Dario Dongo and Andrea Adelmo Della Penna
Footnotes
(1) Marti (2019). Ultra-processed foods are not “real food” but really affect your health. Nutrients 11: 1902, doi: 10.3390 / nu11081902
(2) Monteiro et al. (2019). Ultra-processed foods: what they are and how to identify them. Public Health Nutr. 22: 936-941, doi: 10.1017 / S1368980018003762
(3) Bleiweiss-Sande et al. (2019). Robustness of food processing classification system. Nutrients 11: 1344, doi: 10.3390 / nu11061344
(4) Fardet et al. (2018) Characterization of the degree of food processing in relation to its health potential and effects. Adv. Food Nutr. 85: 79129, doi: 10.1016 / bs.afnr.2018.02.002
(5) It costs et al. (2019) Ultra-processed food consumption and its effects on anthropometric and glucose profile: a longitudinal study during childhood. Nutr. Metab. Cardiovasc. Dis. 29: 177-184, doi: 10.1016 / j.numecd.2018.11.003
(6) Rico-Campà et al. (2019) Association between consumption of ultra-processed foods and all cause mortality: SUN prospective cohort study. BMJ 365: I1949, https://doi.org/10.1136/bmj.l1949
(7) Srour et al. (2019) Ultra-processed food intake and risk of cardiovascular disease: Prospective cohort study (NutriNet-Santé). BMJ 365: I1451, https://doi.org/10.1136/bmj.l1451
(8) Rauber et al. (2018) Ultra-processed food consumption and chronic non-communicable diseases-related dietary nutrient profile in the UK (2008-2014). Nutrients 10: 587, doi: 10.3390 / nu10050587
(9) Lawrence et al. (2019). Ultra-processed food and adverse health outcomes. BMJ 365: I2289, https://doi.org/10.1136/bmj.l2289
(10) Odeja-Rodriguez et al. (2018). Aging, telomere integrity, and antioxidant food. In Obesity: oxidative stress and dietary antioxidants. 1st edition Cambridge, MA: Elsevier pp. 241-61, https://doi.org/10.1016/B978-0-12-812504-5.00012-X
(11) O’Donovan et al. (2011) Cumulative inflammatory load is associated with short leukocyte telomere length in the health, aging and body composition study. PLoS One 6 (5): e19687, doi: 10.1371 / journal.pone.0019687
(12) Zgheib et al. (2018) Short telomere length is associated with aging, central obesity, poor sleep and hypertension in Lebanese individuals. Aging Dis. 9:77, doi: 10.14336 / AD.2017.0310
(13) Alonso-Pedrero et al. (2020). Ultra-processed food consumption and the risk of short telomeres in an elderly population of the Seguimiento Universidad de Navarra (SUN) Project. AM. J. Clin. Nutr. 00: 1-8, doi: 10.1093 / ajcn / nqaa075
(14) Galie et al. (2019) Impact of nutrition on telomere health: Systematic review of observational cohort studies and randomized clinical trials. Adv. Nutr. 00: 1-26, https://doi.org/10.1093/advances/nmz107
(15) Galilee-Zabalza et al. (2018). Mediterranean diet and quality of life: baseline cross-sectional analysis of the PREDIMED-PLUS trial. PLoS One 13 (6): e0198974, doi: 10.1371 / journal.pone.0198974
(16) Boccardi et al. (2013). Mediterranean diet, telomere maintenance and health status among the elderly. PLoS One 8 (4): e62781, doi: 10.1371 / journal.pone.0062781
(17) Carlos et al. (2018). Mediterranean Diet and health outcomes in the SUN cohort. Nutrients 10: 439, doi: 10.3390 / nu10040439
(18) Crous-Bou et al. (2014) Mediterranean diet and telomere length in Nurses’ Health Study: population based cohort study. BMJ 349: g6674, doi: 10.1136 / bmj.g6674
(19) Davinelli et al. (2019). The potential nutrigeroprotective role of Mediterranean diet and its functional components on telomere length dynamics. Aging Res. Rev. 49: 1-10, doi: 10.1016 / j.arr.2018.11.001
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE – GIFT – Food Times) and Égalité.
Graduated in Food Technologies and Biotechnologies, qualified food technologist, he follows the research and development area. With particular regard to European research projects (in Horizon 2020, PRIMA) where the FARE division of WIISE Srl, a benefit company, participates.