The impact of vegetable and fruit consumption on mortality in persons aged 65 years and older: results of a prospective cohort study
- Authors: Turusheva A.V.1, Pronina D.V.1, Shchukina A.M.1, Lepa V.E.1
-
Affiliations:
- North-Western State Medical University named after I.I. Mechnikov
- Issue: Vol 28, No 2 (2024)
- Pages: 61-68
- Section: Original studies
- Submitted: 03.05.2024
- Accepted: 05.05.2024
- Published: 15.07.2024
- URL: https://journals.eco-vector.com/RFD/article/view/631569
- DOI: https://doi.org/10.17816/RFD631569
- ID: 631569
Cite item
Abstract
BACKGROUND: High consumption of vegetables and fruits is associated with a reduced risk of developing cardiovascular diseases, type 2 diabetes mellitus, cancer and all — causes mortality. However, most studies on the health benefits of fruit and vegetable consumption have traditionally focused on children, adolescents, young and middle-aged people, and only a few of them included older adults, and even more so did not take into account the geriatric status of the study participants.
AIM: To assess the effect of fruit and vegetable consumption on mortality in Russian population people 65 years and older.
MATERIALS AND METHODS: A prospective cohort study of a random sample of individuals aged 65 years and older (n = 383). The main parameters of the study: Mini Nutritional Assessment anthropometry, clinical blood test, albumin, total protein, C-reactive protein, comprehensive geriatric assessment, 2.5 years of follow-up.
RESULTS: The average age of the participants was 77.7 ± 5.7 years. The frequency of fruit and vegetable consumption was higher among women, compared with men by 16.7% (95% confidence interval 1.5–33.6%). Consumption of 2 or more portions vegetables and/or fruits per day was associated with a reduced risk of death from all causes with hazard ratio 0.401 (95% confidence interval 0.180–0.896) after adjusting for gender, age of study participants, presence of malnourishment syndrome, protein intake, glasses drunk per day, body mass index, reduced middle arm circumstance, falls, cognitive status, autonomy decline and a decrease in the level of physical function.
CONCLUSIONS: Consumption of 2 or more portions of vegetables and/or fruits per day was independently associated with a 59.9% reduction in the risk of death from all causes in persons aged 65 years and older.
Keywords
Full Text
BACKGROUND
A diet rich in fruits and vegetables is associated with reduced risk of cardiovascular disease, type 2 diabetes, cancer, and all-cause mortality. The World Health Organization recommends that individuals consume at least five servings of fruits and vegetables (approximately 400 grams) daily, in addition to sweet potato, cassava, and other starchy vegetables1.
The special nutritional needs of the older adults require specific adaptations of clinical nutrition guidelines. However, most studies on the health benefits of fruit and vegetable consumption have focused on children, adolescents, young and middle-aged people, and few have included older adults, and the existing studies did not consider the geriatric status of the participants [1, 2].
This study aimed to evaluate the effect of fruit and vegetable consumption on mortality in the Russian population aged ≥65 years.
MATERIALS AND METHODS
Study design
The study was based on the analysis of the results of the second screening of the prospective cohort study “Crystal,” which involved a random sample of individuals aged ≥65 years. The first screening was conducted in 2009 (n = 611) and the second screening in 2011–2012. In total, 130 individuals declined to participate in the second screening, 98 died before the second screening, and 4 died during the second screening and did not have time to complete the full range of diagnostic tests. However, they completed the nutritional assessment questionnaire and were therefore included in the analysis. The main clinical and demographic characteristics obtained at the first screening were compared between those who declined to participate in the subsequent screening and those who agreed to participate in the second screening to identify any potential errors associated with refusal to participate in the subsequent screening. No significant differences were observed. The total followup period was 30.9 (26.6 ± 6.1) months. The study design has been described in more detail previously [3].
The participants provided informed consent to participate in the study.
Main survey parameters
The nutritional pattern analysis included the following parameters:
- Nutritional status was evaluated using the Mini Nutritional Assessment. Individuals scoring ≤23.5 points were classified as having malnutrition syndrome, whereas those scoring >23.5 points were described as having normal nutritional status [4].
- Data regarding the frequency of fruit and vegetable consumption, in addition to protein and fluid intake, were obtained from the Mini Nutritional Assessment (answers to questions marked with an “M”). One serving of vegetables was defined as a medium-sized vegetable (75 g) and one serving of fruit as one medium-sized fruit (150 g) [4].
- Anthropometric assessment was performed based on measurements of body weight, height, mid upper arm circumference (MUAC), and triceps skinfold thickness (TSFT). Mid arm muscular area (MAMA) was calculated using the formula:
MAMA = MUAC – 0,314*TSFT.
- Body mass index (BMI) was calculated as the ratio of body weight in kilograms to height in meters squared. Individuals with a BMI <18.5 kg/m² were classified as underweight, those with a BMI between 18.5 and 24.9 kg/m² as having a normal weight, and those with a BMI between 25.0 and 29.9 kg/m² as overweight. The classification of obesity was as follows: obese I degree, 30.0–34.9 kg/m²; obese II degree, 35.0–39.9 kg/m²; and obese III degree, ≥40 kg/m².
- Laboratory tests included a complete blood count test, total protein, albumin, and C-reactive protein levels.
Furthermore, the patients were examined for comorbidities and therapy by interview and review of medical records, functional status (The Short Physical Performance Battery and grip strength), autonomy (The Barthel index), emotional status (The Geriatric Depression Scale), cognitive function (The Mini Mental State Examination), sensory deficits, urinary incontinence, and falls in the past year [4, 5].
Statistical analysis
Means and standard deviations (M ± SD) were used to analyze continuous data. The Mann–Whitney test, χ², and the comparison of proportions test were applied to assess differences between groups. Kaplan–Meier survival curves and multinomial Cox regression were employed to evaluate the association between the number of servings of fruit and/or vegetables consumed and mortality in the study population. The critical limit of validity was considered to be p = 0.05.
Basic statistical calculations were performed using SPSS 26.0 (SPSS Inc., USA) and MedCalc 19.5.3 (MedCalc Software Ltd.).
RESULTS
This study included 383 participants aged 68–94 years, with a mean age of 77.7 ± 5.7 years. Of these, 24.8% (n = 95) were male. Two or more servings of vegetables and/or fruits per day were consumed by 90.8% (n = 348) of the individuals. The frequency of fruit and vegetable consumption was 16.7% (95% confidence interval (CI), 1.5%–33.6%) higher in women than in men.
Figure. Kaplan–Meier curves to estimate survival at different levels of fruit and vegetable consumption per day over 2.5 years of follow-up (n = 383)
Рисунок. Кривые Каплана – Мейера для оценки выживаемости при разных уровнях потребления фруктов и овощей в день в течение 2,5 лет наблюдения (n = 383)
During 2.5 years of followup, 13.1% (n = 50) of the individuals died. When the influence of dietary composition on mortality was analyzed, a reduction in mortality risk was observed in individuals who consumed two or more servings of vegetables and/or fruits per day (Figure).
No significant differences were found in the prevalence of chronic noncommunicable diseases and geriatric syndromes in individuals who consumed both less than two servings and two servings or more of fruits and/or vegetables per day, except for differences in the prevalence of malnutrition and falls (Table). The prevalence of falls in the group of individuals consuming less than two servings of vegetables and/or fruits per day was 21.7 (95% CI: 5.8–38.3) higher, and malnutrition was 27.7 (95% CI: 10.7–43.4) higher. This difference remained significant after adjustment for sex and age. Individuals who consumed less than two servings of vegetables and/or fruit per day were more likely to have lower protein intake, lower BMI, and low MAMA (Table).
Table. Clinical and demographic characteristics of study participants with different amounts of portions of vegetables and fruits intake per day (n = 383)
Таблица. Клинико-демографическая характеристика лиц, потребляющих разное количество порций овощей и фруктов в день (n = 383)
Indicators | Consuming less than two servings of vegetables and/or fruits per day (n = 35) | Consuming two servings of vegetables and/or fruits or more per day (n = 348) | Level p |
Men, n (%) | 14 (40.0) | 81 (23.3) | 0.028 |
Age, mean and standard deviation, years | 76.9 ± 5.5 | 77.0 ± 5.7 | 0.056 |
Examined at home, n (%) | 12 (35.3) | 111 (32.2) | 0.422 |
Frequency of chronic diseases | |||
Myocardial infarction, n (%) | 9 (26.5) | 51 (14.8) | 0.068 |
Stroke, n (%) | 6(17.6) | 72 (20.9) | 0.426 |
Atrial fibrillation, n (%) | 18 (52.9) | 144 (41.7) | 0.141 |
Type 2 diabetes mellitus, n (%) | 7 (20.6) | 76 (22.0) | 0.528 |
Chronic obstructive pulmonary disease, n (%) | 6 (17.6) | 16 (17.7) | 0.606 |
Asthma, n (%) | 3 (8.8) | 19 (15.5) | 0.315 |
Cancer, n (%) | – | 19 (5.5) | 0.160 |
Peripheral artery disease, n (%) | 8 (23.5) | 86 (24.9) | 0.532 |
Arthritis/arthrosis, n (%) | 24 (70.6) | 285 (82.8) | 0.068 |
Frequency of geriatric syndromes | |||
Falls, n (%) | 15(45.5) | 82(23.8) | 0.008 |
Fractures, n (%) | 4 (11.4) | 41 (11.9) | 0.620 |
Visual impairment, n (%) | 27 (79.4) | 301 (87.2) | 0.155 |
Hearing loss, n (%) | 4 (11.8) | 33 (9.6) | 0.430 |
Autonomy decline, n (%) | 10 (29.4) | 86 (25.1) | 0.355 |
Not leaving the house for walks, n (%) | 5 (14.7) | 57 (16.6) | 0.501 |
Barthel index <95, n (%) | 9 (26.5) | 64 (18.6) | 0.187 |
Urinary incontinence, n (%) | 20 (58.8) | 145 (42.0) | 0.042 |
Short Physical Performance Battery <8, n (%) | 18 (56.5) | 149 (50.5) | 0.334 |
Grip strength <10th centile, n (%) | 10 (29.5) | 19 (26.1) | 0.408 |
Depression, n (%) | 13 (38.2) | 137 (39.9) | 0.500 |
The Mini Mental State Examination: · 30–28 points, n (%) · 27–24 points, n (%) <24 points, n (%) |
12 (35.3) 8 (23.5) 14 (41.2) |
142 (41.3) 84 (24.4) 118 (34.3) | 0.410 |
Nutritional status | |||
Body mass index: · <18.5 kg/m², n (%) · 18.5–24.9 kg/m², n (%) · 25.0–29.9 kg/m², n (%) · 30.0–34.9 kg/m², n (%) · 35.0–39.9 kg/m², n (%) · >40.0 kg/m², n (%) |
1 (2.9) 10 (29.4) 13 (38.2) 8 (23.5) 2 (5.9) – |
5 (1.4) 56 (16.1) 147 (42.2) 97 (27.9) 33 (9.5) 10 (2.9) | |
Anemia, n (%) | 11 (32.4) | 88 (25.4) | 0.246 |
C-reactive protein <5 mg/L, n (%) | 10 (30.3) | 73 (21.0) | 0.156 |
Total protein <60 g/L, n (%) | – | 10 (2.9) | 0.388 |
Albumin <35 g/L, n (%) | 2 (5.7) | 12 (3.5) | 0.360 |
Protein food intake, n (%): · One serving of dairy products (1 cup milk, 60 g cottage cheese, 30 g cheese, and 3/4 cup yogurt) per day, n (%) · Two or more servings of legumes and eggs per week (1 serving of 200 g legumes and 1 egg), n (%) · Meat, fish, or poultry every day, n (%) |
11 (31.4)
13 (37.1)
11 (31.4) |
28 (8.0)
123 (35.3)
197 (56.6) | 0.000 |
Fluid intake: · <3 cups (0 points), n (%) · 3–5 cups (0.5 points), n (%) · •>5 cups (1 point), n (%) |
3 (8.6) 23 (65.7) 9 (25.7) |
9 (2.6) 190 (54.6) 149 (42.8) | 0.017 |
Number of meals per day: 1, n (%) 2, n (%) 3, n (%) |
– 1 (2.9) 34 (97.1) |
1 (0.3) 48 (13.8) 299 (85.9) | 0.062 |
Malnutrition, n (%) | 19 (55.9) | 98 (28.2) | 0.001 |
Low Mid Arm Muscular Are, n (%) | 10 (29.4) | 54 (15.6) | 0.040 |
Malnutrition syndrome, low BMI, and inadequate protein food and fluid intake may have increased the risk of all-cause mortality in the group of individuals who consumed less than two servings of vegetables and/or fruits per day. However, the association with a high risk of mortality during 2.5 years of followup remained significant even after adjustment for gender, age, malnutrition, amount of protein food and fluid intake per day, BMI, low MAMA, and fall syndrome (HR: 0.446; 95% CI: 0.203–0.977). The link between reduced risk of all-causes mortality and high fruit and/or vegetable consumption remained significant after additional adjustment for cognitive status, loss of autonomy, falls in the past year, and low physical functioning (HR: 0.401; 95% CI: 0.180–0.896).
DISCUSSION
Based on the study results, consumption of two or more servings of vegetables and/or fruit per day was shown to reduce the risk of mortality by 59.9% over a 2.5-year followup period in people aged ≥65 years, regardless of nutritional and geriatric status.
The association between mortality and fruit and vegetable consumption has been reported in other studies [1, 2]. Two meta-analyses showed that the lowest risk of mortality was associated with consumption of two fruits and three vegetables per day [1, 2]. Eating one fruit per day reduced the risk of all-cause mortality by 6%, and eating one vegetable per day reduced the risk by 5% [2].
The present study does not show a beneficial effect of consuming two or more servings of vegetables and/or fruit per day on reducing the risk of cardiovascular disease, as has been shown in other population-based studies [6–8]. In a meta-analysis of eight prospective cohort studies, individuals who consumed five or more servings of vegetables and/or fruit per day had a 26% lower risk of stroke than those who consumed less than three servings of vegetables and/or fruit per day [6]. Another meta-analysis of nine prospective cohort studies reported a 4% reduction in the risk of coronary heart disease for each additional serving of fruit and vegetables per day, with the standard serving calculated as 106 g [7]. In the present study, the lack of association between fruit and vegetable intake and cardiovascular disease risk reduction may be due to several factors.
For example, there are regional differences in the types of fruits and vegetables consumed. Different varieties, grown under different conditions, contain different combinations and concentrations of vitamins and minerals and have different effects on the health of the older population. According to studies, vitamin C, vitamin E and its derivatives, carotenoids (alpha- and beta-carotene, beta-cryptoxanthin and lycopene), and potassium have the most pronounced effect on reducing the risk of cardiovascular disease and mortality [5]. Additionally, the amount of fruits and vegetables consumed and their variety in the diet play a significant role in reducing cardiovascular risk and mortality from cardiovascular disease [10]. However, in a study by Sun et al., only the presence of bananas and apples in the diet influenced the reduction of the risk of mortality during the 10-year followup, whereas the consumption of other fruits, including pears, pineapples, and grapes, which also contain high concentrations of vitamin C, vitamin E, carotenoids, and potassium, did not contribute to the reduction of the risk of mortality [11].
Most researchers who found an association between fruit and vegetable intake and cardiovascular disease risk reduction have used comprehensive dietary questionnaires to assess intake. The present study used the Mini Nutritional Assessment, which was developed to detect malnutrition and does not adequately assess the amount of fruits and vegetables consumed per day. These questionnaires can identify those who consume two or more or less than two servings of fruits and vegetables per day. However, the exact proportion of people in the group who consume less than two servings or one serving of fruits and vegetables per day and who do not consume fruits and vegetables at all remains unknown.
The strengths of this study were its prospective observational study design, random sampling, and comprehensive geriatric assessment analysis. These elements may have contributed to the higher mortality rates among individuals who consumed less than two servings of vegetables and/or fruit per day.
CONCLUSIONS
Consuming two servings or more of vegetables and/or fruits is an independent factor in reducing the risk of all-cause mortality in persons aged ≥65 years.
ADDITIONAL INFORMATION
Funding source. The first examination in the Crystal study was carried out with the support of the Grant of the President of the Russian Federation No. 192-RP, the second — without funding.
Competing interests. The authors declare that they have no competing interests.
Author contribution. All authors made a substantial contribution to the conception of the study, acquisition, analysis, interpretation of data for the work, drafting and revising the article, final approval of the version to be published and agree to be accountable for all aspects of the study.
Personal contribution of each author: A.V. Turusheva — concept and design of the study, data analysis, text writing, editing; V.E. Lepa, D.V. Pronina, А.М. Shchukina — literature review, text writing.
Ethics approval. The present study protocol was approved by the local Ethics Committee of the North-Western State Medical University named after I.I. Mechnikov (No. 1 dated 22.01.2014).
ДОПОЛНИТЕЛЬНАЯ ИНФОРМАЦИЯ
Источник финансирования. Первое обследование в исследование «Хрусталь» выполнено при поддержке гранта Президента Российской Федерации № 192-RP, второе — без финансирования.
Конфликт интересов. Авторы декларируют отсутствие явных и потенциальных конфликтов интересов, связанных с публикацией настоящей статьи.
Вклад авторов. Все авторы внесли существенный вклад в разработку концепции, проведение исследования и подготовку статьи, прочли и одобрили финальную версию перед публикацией.
Наибольший вклад распределен следующим образом: А.В. Турушева — концепция и дизайн исследования, анализ данных, написание текста, редактирование; В.Е. Лепа, Д.В. Пронина, А.М. Щукина — обзор литературы, написание текста.
Этический комитет. Протокол исследования был одобрен локальным этическим комитетом СЗГМУ им. И.И. Мечникова (№ 1 от 22.01.2014).
1 Healthy Eating // WHO. Available online: https://www.who.int/ru/news-room/fact-sheets/detail/healthy-diet. Accessed on 02.05.2024.
About the authors
Anna V. Turusheva
North-Western State Medical University named after I.I. Mechnikov
Author for correspondence.
Email: anna.turusheva@gmail.com
ORCID iD: 0000-0003-3347-0984
SPIN-code: 9658-8074
Scopus Author ID: 57189466350
ResearcherId: U-3654-2017
MD, Dr. Sci. (Med.), Assistant Professor
Russian Federation, 41 Kirochnaya St., Saint Petersburg, 191015Daria V. Pronina
North-Western State Medical University named after I.I. Mechnikov
Email: pronina25072000@mail.ru
ORCID iD: 0009-0007-2902-9770
41 Kirochnaya St., Saint Petersburg, 191015
Alla M. Shchukina
North-Western State Medical University named after I.I. Mechnikov
Email: allashchukina.12@gmail.com
ORCID iD: 0009-0009-0844-550X
Russian Federation, 41 Kirochnaya St., Saint Petersburg, 191015
Victoria E. Lepa
North-Western State Medical University named after I.I. Mechnikov
Email: vika.lepa02@gmail.com
ORCID iD: 0009-0006-7643-1159
Russian Federation, 41 Kirochnaya St., Saint Petersburg, 191015
References
- Wang DD, Li Y, Bhupathiraju SN, et al. Fruit and vegetable intake and mortality: results from 2 prospective cohort studies of US men and women and a meta-analysis of 26 cohort studies. Circulation. 2021;143(17):1642−1654. doi: 10.1161/CIRCULATIONAHA.120.048996
- Wang X, Ouyang Y, Liu J, et al. Fruit and vegetable consumption and mortality from all causes, cardiovascular disease, and cancer: systematic review and dose-response meta-analysis of prospective cohort studies. BMJ. 2014;349:g4490. doi: 10.1136/bmj.g4490
- Turusheva A, Frolova E, Hegendoerfer E, Degryse JM. Predictors of short-term mortality, cognitive and physical decline in older adults in northwest Russia: a population-based prospective cohort study. Aging Clin Exp Res. 2017;29(4):665−673. doi: 10.1007/s40520-016-0613-7
- Senile asthenia. Clinical recommendations. Moscow, 2021. 170 p. Available from: https://static-0.minzdrav.gov.ru/system/attachments/attaches/000/059/119/original/10.старческая астения.2021.pdf?1641888380. Accessed: 02 May, 2024. (In Russ.)
- Turusheva AV, Frolova EV, Degryse J. Development of reference ranges of handgrip strength among healthy adults 65+ in Northwest Russia: a prospective population-based cohort Crystal study. Russian Family Doctor. 2017;21(4):29−35. EDN: YMQKLK doi: 10.17816/RFD2017429-35
- He FJ, Nowson CA, MacGregor GA. Fruit and vegetable consumption and stroke: meta-analysis of cohort studies. Lancet. 2006;367(9507):320−326. doi: 10.1016/S0140-6736(06)68069-0
- Dauchet L, Amouyel P, Hercberg S, Dallongeville J. Fruit and vegetable consumption and risk of coronary heart disease: a meta-analysis of cohort studies. J Nutr. 2006;136(10):2588−2593. doi: 10.1093/jn/136.10.2588
- Mukaneeva DK, Kontsevaya AV, Karamnova NS, et al. Economic burden of insufficient consumption of vegetables and fruits in Russia. Ekologiya cheloveka. 2020;(9):28−35. EDN: BSTMUT doi: 10.33396/1728-0869-2020-9-28-35
- Barclay AW, Petocz P, McMillan-Price J, et al. Glycemic index, glycemic load, and chronic disease risk – a meta-analysis of observational studies. Am J Clin Nutr. 2008;87:627−637. doi: 10.1093/ajcn/87.3.627
- Aljadani HM, Patterson A, Sibbritt D, et al. Frequency and variety of usual intakes of healthy foods, fruit, and vegetables predicts lower 6-year weight gain in young women. Eur J Clin Nutr. 2020;74(6):945−952. doi: 10.1038/s41430-019-0532-8
- Sun C, Li J, Zhao Z, et al. The correlation between fruit intake and all-cause mortality in hypertensive patients: a 10-year follow-up study. Front Nutr. 2024;11:1363574. doi: 10.3389/fnut.2024.1363574