Flavonoid intake and long-term risk of coronary heart disease and cancer in the seven countries study.

OBJECTIVE: To determine whether flavonoid intake explains differences in mortality rates from chronic diseases between populations. DESIGN: Cross-cultural correlation study. SETTING/PARTICIPANTS: Sixteen cohorts of the Seven Countries Study in whom flavonoid intake at baseline around 1960 was estimated by flavonoid analysis of equivalent food composites that represented the average diet in the cohorts. MAIN OUTCOME MEASURES: Mortality from coronary heart disease, cancer (various sites), and all causes in the 16 cohorts after 25 years of follow-up. RESULTS: Average intake of antioxidant flavonoids was inversely associated with mortality from coronary heart disease and explained about 25% of the variance in coronary heart disease rates in the 16 cohorts. In multivariate analysis, intake of saturated fat (73%; P = 0.0001), flavonoid intake (8%, P = .01), and percentage of smokers per cohort (9%; P = .03) explained together, independent of intake of alcohol and antioxidant vitamins, 90% of the variance in coronary heart disease rates. Flavonoid intake was not independently associated with mortality from other causes. CONCLUSIONS: Average flavonoid intake may partly contribute to differences in coronary heart disease mortality across populations, but it does not seem to be an important determinant of cancer mortality.

Vitamin C status in chronic schizophrenia.

Schizophrenic patients on the same hospital diet as control group subjects had significantly lower levels of fasting plasma vitamin C (p less than 0.05) and 6-hr urinary vitamin C excretion after an ascorbic acid load test (p less than 0.01). After administration of 70 mg of ascorbic acid for 4 weeks there was no longer any difference in plasma vitamin C levels between schizophrenics and control group subjects, but the urinary vitamin C excretion after the vitamin C loading test remained significantly lower in schizophrenics (p less than 0.05). The administration of 1 g ascorbic acid for 4 weeks, in addition to eliminating differences in the plasma vitamin C level, also increased the urinary vitamin C excretion of schizophrenic patients to the level of the control group subjects. The results of this study are in agreement with the hypothesis that schizophrenic patients require higher levels of vitamin C than the suggested optimal ascorbic acid requirement for healthy humans.

Growth and development of three Yugoslav populations in different ecological settings.

The role of genetical and ecological factors in the physical growth and development was studied in three Yugoslav populations living in different ecological settings. Anthropometric measurements of 6,908 children and young adolescents ages 1 to 18 years were taken and the results were compared in regard to ethnic and ecological characteristics. The evidence is presented that significant improvement in physical characteristics follows the improvement in environmental factors including nutrition. In addition to an increase in body height, changes were also noted in the build of the bony frame of the population living under improved environmental conditions. There was a change in the shape of the skeleton from the squatty appearance of the short population to the more lanky shape of the tall population. It is concluded that systematic periodic collection of the information on child growth could serve as a useful monitoring system for the surveillance of ecological and nutritional trends of a country.

Zinc nutrition and taste acuity in school children with impaired growth.

A study on the relationship between zinc nutrition status and the parameters of growth and physical development was carried out in a group of school children aged 9 to 12 years, selected from a population showing a higher prevalence of "below average" hair zinc concentrations. The growth of the children was assessed as the attained height for age in comparison with the reference population median, whereas the physical development was assessed on the basis of the weight for height and upper arm circumference. Taste acuity was also examined. The results showed an increased prevalence of the "below average" and "low" zinc values in hair and plasma in children of shorter stature and poorer nutrition status. The examination of taste acuity has shown that the occurrence of moderate to severe hypogeusia was statistically significantly associated with the reduction of hair zinc content. The children with moderate and more severe hypogeusia also belonged to the most poorly nourished in the examined population.

Bone status and fracture rates in two regions of Yugoslavia.

Bone status and fracture rates were evaluated in two Yugoslav populations with very different dietary habits. In district A (Podravina) the daily calcium intake was about twice that in district B (Istra). There were similar but smaller differences in the intakes of other nutrients. In district B metacarpal cortical width was reduced in all age groups of both sexes but the difference tended to decrease with age. The proximal femur fracture rate was higher in district B than district A but there was no difference between the forearm fracture rates in the two districts. Our results confirm that bone mass at any age is clearly the result of age and sex and most probably other genetically determined factors but also show that this expression is nutrition related. The data suggest that nutrition (in particular the calcium intake) is an important determinant of bone mass in young adults but seems to have little effect on age-related bone loss in either males or females. The main determinant of cortical bone mass in the elderly seems to be the cortical bone mass in middle life. The proximal femur fractures of old people reflect declining cortical bone mass but the distal forearm fractures of middle-aged women are unrelated to cortical bone mass or nutritional status.

Food consumption patterns in the 1960s in seven countries.

At the end of the 1950s the Seven Countries Study was designed to investigate the relations between diet and cardiovascular diseases. Sixteen cohorts were selected in Finland, Greece, Italy, Japan, The Netherlands, United States, and Yugoslavia. During the 1960s food consumption data were collected from random samples of these cohorts by use of the record method. In Finland the intake of milk, potatoes, edible fats, and sugar products was very high. A similar but lower intake pattern was observed in The Netherlands. Fruit, meat, and pastry consumption was high in the United States; cereal and alcoholic drink consumption was high in Italy; and bread consumption high in Yugoslavians except for those in Belgrade. In Greece the intake of olive oil and fruit was high and the Japanese cohorts were characterized by a high consumption of fish, rice, and soy products. These differences in food consumption patterns have lessened during the past 25 y.

Effect of industrial pollution on seafood content and dietary intake of total and methylmercury.

The total mercury and methylmercury content of seafood was studied in an area of the Adriatic Sea polluted with inorganic mercury from a local industrial plant. The industrial pollution has affected both the total and the methylmercury content of seafood, but only the difference in the total mercury level was statistically significant when compared with a control area with no local industry. Studies of seafood consumption patterns indicate that, when the subjects examined from both areas were matched by their seafood consumption, both total mercury and methylmercury intake was higher in the industrially polluted area. The percentage of subjects ingesting total mercury above the WHO Provisional Weekly Tolerance Intake (PWTI) of 300 micrograms was also higher in the industrially polluted area. However, the percentage of subjects whose methylmercury intake was above the PWTI of 200 micrograms was higher in the control area, primarily due to the increased number of subjects consuming fish more than 5 times a week.

Dietary mercury intake and human exposure in an Adriatic population.

A study was conducted to examine human exposure to mercury through dietary mercury intake in a population living in an industrially non-polluted area of the Adriatic Sea. The results have shown that approximately 20% of the subjects had a weekly dietary mercury intake above the provisional tolerable weekly intake (PTWI), primarily those consuming fish and other seafood > 6 times/week. The estimated seafood consumption corresponding to a mean intake of PTWI of 300 micrograms total mercury was 1559 g, and 1365 g for a PTWI of 200 micrograms methylmercury. However, the total mercury content in hair in individuals consuming total mercury above the PTWI was in the range of 1.3-12.9 micrograms/g, whereas the methylmercury content in hair in subjects consuming methylmercury above the PTWI was between 1.1-10.8 micrograms. Thus, the mercury content in hair did not reach the critical level at which toxic effects of mercury could be expected. The results, particularly those related to methylmercury exposure, did not differ significantly from data reported earlier from an industrially polluted area, thus indicating that the mercury content of fish and consequent human exposure to mercury reflects primarily the general ecological characteristics of the Adriatic, rather than the impact upon a specific local pollution.

Effects of pyridoxine and riboflavin supplementation on physical fitness in young adolescents.

The effects of pyridoxine and riboflavin supplementation on physical fitness was studied in a group of children with higher prevalence of subclinical, biochemically defined pyridoxine and riboflavin deficiencies. One hundred and thirteen children aged 12-14 years were allocated to three groups to receive daily (except Sundays) for two months either a placebo or a supplement of pyridoxine or riboflavin. The supplementation resulted in marked improvement of pyridoxine and riboflavin nutrition status and was followed by disappearance of respective biochemical deficiencies. The improvement in pyridoxine biochemical status was also accompanied by a slight and statistically significant increase in physical fitness (p less than 0.05) assessed by bicycle ergometer technique. The increase in physical fitness in the riboflavin supplemented group was statistically non-significant (p greater than 0.05). In both supplemented groups there was a significant increase in physical fitness in subjects with initially deficient biochemical vitamin status whereas supplementation had no effect on physical fitness in subjects with initially high biochemical values.

The effects of riboflavin administration on iron metabolism parameters in a school-going population.

The effect of riboflavin administration on iron metabolism was studied in a group of riboflavin-deficient children with Erythrocyte Glutathione Reductase (EC 1.6.4.2) reactivation above 1.20. The results have shown that the administration of riboflavin has resulted in a decrease of serum iron as well as in transferrin saturation which was accompanied by an increase in blood hemoglobin in subjects with initially lower hemoglobin values (less than or equal to 13.5 g/100 ml). There was, however, no change in blood hemoglobin in the group with initially higher hemoglobin values (greater than or equal to 14.0 g/100 ml). The results suggest that inadequate riboflavin intake may affect the iron utilization. The possible mechanism of riboflavin action on iron utilization is discussed.

Vitamin C status and physical working capacity in adolescents.

The effect of ascorbic acid supplementation on physical working capacity was studied in young adolescent boys in which the concomitant biochemical riboflavin and pyridoxin deficiencies were corrected by medicamentous prophylaxis. After daily administration for two months of 70 mg ascorbic acid, the mean plasma vitamin C in the experimental group (n = 49) rose from 0.33 to 1.49 mg/dl (p less than 0.001) and the prevalence of deficient plasma vitamin C values (less than 0.20 mg/dl) decreased from 52.3 percent to zero. The improvement in vitamin C biochemical status was also accompanied by a statistically significant increase in VO2 max. (p less than 0.01). There were no significant changes neither in the mean plasma vitamin C values nor in the mean VO2 max. in the control group subjects (n = 42). The increase in VO2 max. in the experimental group was primarily the result of an increase of VO2 max. in subjects with initially lower values. When data from both experimental and control groups were pooled together, a positive and significant association was found between VO2 max. and the increase of plasma vitamin C values below 1.0 mg/dl. No further increase in VO2 max. was observed when vitamin C plasma values reached 1.0 mg/dl or more. The two regression lines crossed at X = 0.86 mg/dl. This cut off point of plasma vitamin C level corresponds to a dietary intake of about 80 mg of ascorbic acid per day. The results of this study are in agreement with the suggested optimal ascorbic acid daily intake obtained by kinetic studies with (1-14C) ascorbic acid.

The effect of ascorbic acid supplementation on periodontal tissue ultrastructure in subjects with progressive periodontitis.

In an attempt to determine the optimal daily ascorbic acid requirement, the effect of different levels of ascorbic acid intake on collagen synthesis was studied in a double-blind experimental design. By use of electron microscopy, interproximal gingival tissue sections in subjects consuming between 20 to 35 mg of ascorbic acid daily were examined before and after the administration of tablets containing 70 mg of ascorbic acid. The results showed that practically all subjects were affected by progressive periodontitis with marked changes in the connective tissue of the gingival lamina propria. After six weeks of supplementation with ascorbic acid, differences in the shape and activity of fibroblasts in the regenerative tissue of lamina propria were observed. This has resulted in the increased number of collagen bundles in fibroblasts' periphery, increased tonofibril content and an enlarged number of desmosomes between adjacent cells. It is concluded that the obtained results, though suggesting that the optimal daily ascorbic acid intake should be set above the presently recommended 30-50 mg, have to be quantified by a more objective analytical method.

Nutritional status, grip strength, and immune function in institutionalized elderly.

The effects of vitamin supplementation on grip strength and immune function was studied in a group of institutionalized elderly with a relatively higher prevalence of low and below acceptable biochemical parameters of vitamin C, pyridoxine, folic acid, riboflavin, iron and zinc nutriture. The vitamin supplementation has resulted in a statistically significant increase in the level of biochemical parameters related to added vitamins, and the number of subjects with inadequate vitamin values was reduced to zero. The improved vitamin status had a positive and statistically significant effect on the delayed cutaneous hypersensitivity one of the parameters of cellular immunity. The calculation of multiple correlation after inclusion of all biochemical parameters into the stepwise regression analysis has shown that the coefficient of multiple regression between examined biochemical parameters of nutrition status and delayed cutaneous hypersensitivity was R = .599 (p less than 0.001) which indicates that about 36% of the variability in the cellular immunity would be affected by the vitamin and mineral nutrition status.

Increase of gingival hydroxyproline and proline by improvement of ascorbic acid status in man.

The 4-hydroxyproline and proline content of periodontal tissue was measured in 24 adult volunteers with initially low and partially even deficient plasma vitamin C values, before and after peroral supplementation with 70 mg ascorbic acid daily for six weeks. The latter caused a statistically significant rise and normalization respectively of plasma ascorbic acid and simultaneously a statistically significant increase of the hydroxyproline and proline in periodontal tissue (p less than 0.01) but not before the plasma vitamin C level was above 0.9 mg/dl. The optimal plasma vitamin C level which was associated with the highest hydroxyproline and proline content in periodontal tissue ranged between 1.00-1.30 mg/dl corresponding to the total daily dietary ascorbic acid intake of about 100 mg.

Ageing, nutritional status and immune response.

The effects of vitamin supplementation on the age-related decline in immune function was studied in a population of elderly subjects with a high prevalence of low and deficient serum values of vitamin C, vitamin E, riboflavin and pyridoxin, as well as iron and zinc. The immune function was examined by measuring delayed cutaneous hypersensitivity (DCH) after intradermal application of a set of 7 antigens in 72 subjects aged 60-89 years living in two homes for the elderly. The results showed an almost linear statistically significant decline in the DCH test with age (p < 0.01). Vitamin supplementation for a period of 10 weeks significantly improved the biochemical parameters for those vitamins and the age related decline in the DCH test was no longer statistically significant (P > 0.05). No statistically significant changes in DCH were observed in the placebo group. The results of this study suggest that nutrition may be an important determinant of immunocompetence in the elderly.