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In 1981 to 1983, the nutrition and health status of 346 Chinese immigrants in Boston, Mass, aged 60 to 96 years was surveyed and analyzed for cardiovascular risk factors. These elderly Chinese were physically active and seldom obese and consumed a high-carbohydrate (57% of total energy intake), low-fat (24% of total energy intake), low-ascorbic acid (0.62 mmol/d) diet. Current cigarette smoking was common (39%) only in men, while alcoholism was rare in both sexes. Compared with elderly whites, they had lower mean blood pressure and blood levels of total, low-density lipoprotein, and high-density lipoprotein cholesterol, apolipoproteins A-I and B, and ascorbic acid. These characteristics resemble those of the urban population in mainland China, where hemorrhagic stroke is the major cause of cardiovascular mortality.

Lung cancers have been induced in 9 to 53 percent of hamsters given multiple intratracheal instillations of polonium-210 in amounts yielding lifetime exposures of 15 to 300 rads to the lungs. Cigarette smokers have previously been estimated to receive 20 rads to areas of the bronchial epithelium from deposited polonium-210. This finding thus supports the hypothesis that alpha radiation resulting from the polonium-210 or lead-210 present in cigarette smoke may be a significant causative factor in human lung cancer.

Longitudinal data on 1,048 Thai children were evaluated for evidence of subcutaneous fat remodelling. Fat distribution, as defined by 100 (triceps/[triceps + subscapular]), was more pronounced in the limbs during infancy but shifted toward the trunk thereafter. Subsequent stepwise regression analysis indicated that biological age--as measured by Gruelich-Pyle bone age--and weight together explained between 0.8% and 14.5% of variance in fat distribution, with generally larger R2 values over age and for males. Relationships were curvilinear, with sex differences in slope. Path analysis supported the model that weight was a major causal agent primarily after infancy, whereas biological age had a small influence both in infancy and in late childhood. These findings indicate that trunk fat deposition is a normal feature of childhood. They also suggest that hypotheses which associate elevated trunk fatness with disorders of glucose metabolism are invalid for younger children.

Benzo(a)pyrene and 210Po were administered both simultaneously and sequentially by intratracheal instillations to Syrian golden hamsters in experiments designed to identify any synergistic interactions between these carcinogens. Their effects were additive after simultaneous administration. A significant synergistic interaction between the two agents appeared to occur when benzo(a)pyrene exposure followed 4 months after 210Po exposure. Most of this effect could be ascribed, however, to a potentiating effect of subsequent 0.9% NaCl solution instillations on 210Po carcinogenesis. These results emphasize the fact that seemingly innocuous stimuli may significantly potentiate lung carcinogenesis. The implications of these findings in terms of the interactions between alpha-radiation and cigarette smoke in human populations are discussed.

We studied the relationships of supplemental and total vitamin A and supplemental vitamin E intake with fasting plasma biochemical indicators of vitamin A and vitamin E nutritional status among 562 healthy elderly people (aged 60-98 y) and 194 healthy young adult (aged 19-59 y) volunteers. All subjects were nonsmokers. For the young adults, plasma retinol was significantly greater in males than in females (p less than 0.01); retinol was not related to supplemental vitamin A intake for either group. Fasting plasma retinyl esters demonstrated a significant increase with vitamin A supplement use. For supplemental vitamin A intakes of 5001-10,000 IU/d, a 2.5-fold increase over nonusers in fasting plasma retinyl esters was observed for elderly people (p less than 0.05) and a 1.5-fold increase for young adults (p greater than 0.20). For elderly people, greater fasting plasma retinyl esters were associated with long-term vitamin A supplement use (greater than 5 y) and biochemical evidence of liver damage. Elderly people who take vitamin A supplements may be at increased risk for vitamin A overload.

The effect of dose rate on the induction of lung cancer in Syrian hamsters by 5.3 MeV alpha particles was examined by varying the number of weekly intratracheal instillations of carrier-free 210Po. By this technique, most of the radiation dose to the lungs was delivered over intervals ranging from 10 to 120 days. Protraction of exposure over 120 days was slightly more carcinogenic at lower total lung doses (24 rad), but slightly less carcinogenic at higher doses (240 rad), than exposure limited to a 10-day interval. No synergism was observed between very low radiation exposures (2.4 rad) and simultaneously administered benzo[a]pyrene. The carcinogenic effect of a single intratracheal instillation of 210Po in isotonic saline was markedly enhanced by subsequent weekly instillations of 0.2 ml of saline alone, emphasizing the importance of noncarcinogenic secondary factors in the expression of radiation-induced lung cancer.

The relationships between ascorbic acid (plasma and dietary) and plasma HDL cholesterol (HDL-C), total plasma cholesterol (T-C) and T-C:HDL-C ratio were examined in a population of 235 males and 445 females, age 60-98 years. Many known or suspected determinants of HDL-C and T-C, including age, sex, triceps skinfold thickness, fasting blood glucose, alcohol intake, and others, were considered as covariates due to their potential confounding or modifying effects on the relationships under study. The results show that plasma ascorbic acid is significantly (p less than 0.05) correlated with HDL-C (r = 0.09), T-C:HDL-C (r = 0.10), but not with T-C (r = 0.03). There is a strong age interaction with the largest effect of ascorbic acid in the youngest age group studied (60-69 years). The effects of dietary ascorbic acid are similar but slightly reduced in magnitude.

The relationship between biochemical markers of antioxidant status and senile cataract was examined in 112 subjects aged 40 to 70 years. Seventy-seven of these subjects had a cataract in at least one lens. Antioxidant status was measured using erythrocyte superoxide dismutase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase activity, and indexes that included these enzymes plus plasma levels of vitamin E, vitamin C, and carotenoids. Subjects were grouped by level (low, moderate, or high) of the enzymes and antioxidant indexes. Results suggest that subjects with high levels of at least two of the three vitamins (vitamin E, vitamin C, or carotenoids) are at reduced risk of cataract relative to subjects with low levels of one or more of these vitamins (odds ratio, 0.2). The erythrocyte enzymes, either individually or in combination, did not appear to differ between subjects with and without cataract.

Dimethylhydrazine (DMH) induces adenocarcinomas of the colon and rectum in rodents; this animal cancer model system is thought to closely resemble human colorectal cancer. An extract of soybeans containing the Bowman-Birk protease inhibitor added to the diet of DMH-treated mice resulted in a significant suppression of adenomatous tumors of the colonic mucosa. Non-treated mice maintained on the same diet for most of their natural life-span (1.5 years) showed no observable health problems.

This report describes studies in which diets have been developed which when fed to rats commonly result in the formation of primary urinary bladder calculi. The bladder walls of most of these rats but not those without urinary stones were grossly hypertrophied. Microscopic examinations in one of the studies indicated that about a quarter of the bladders containing stones showed histological changes consistent with those characterized as grade I to II transitional cell carcinomas. In all cases animals showing these histological abnormalities consumed vitamin A-deficient diets in which the carbohydrate was supplied mostly by lactose.

The ratio of pepsinogen I to pepsinogen II in the circulation decreases progressively with increasing severity of atrophic gastritis of the fundic gland mucosa. Fasting blood was obtained from 359 free-living and institutionalized elderly people (age range, 60 to 99 years). A pepsinogen I/pepsinogen II ratio less than 2.9, indicating atrophic gastritis, was found in 113 (31.5%) subjects. The prevalence of atrophic gastritis increased significantly with advancing age (P less than .05). Within the atrophic gastritis group, 84 had a pepsinogen I level greater than or equal to 20 micrograms/L, indicating mild to moderate atrophic gastritis, and 29 had a pepsinogen I level less than 20 micrograms/L, indicating severe atrophic gastritis or gastric atrophy. A significant increase in the prevalences of elevated serum gastrin levels (P less than .005), low serum vitamin B12 levels (P less than .005), circulating intrinsic factor antibody (P less than .005), and anemia (P less than .025) was observed with stepwise increases in severity of atrophic gastritis. Subjects with atrophic gastritis exhibited a lower mean serum vitamin B12 level (P less than .05) and a higher mean folate level (P less than .05), but no difference was detected in mean hemoglobin levels or serum levels of iron, ferritin, retinol or alpha-tocopherol. It is concluded that serum pepsinogen I and pepsinogen II levels can be used to determine the prevalence and severity of atrophic gastritis, that atrophic gastritis is common in an elderly population, and that atrophic gastritis is associated with vitamin B12 deficiency and anemia. Further, higher folate levels in atrophic gastritis may be related to an accumulation of 5-methyl tetrahydrofolate in serum due to vitamin B12 deficiency and/or greater folate synthesis by the intestinal flora resulting from bacterial overgrowth secondary to hypo- or achlorhydria.

As part of a nutritional status survey of 691 non-institutionalized men and women aged 60 years and older, supplement use was reported by 45% of the males and 55% of the females. Supplement use was more prevalent in females than males at each age decade. Vitamins C and E were the most commonly used supplements. Mean dietary nutrient intakes were calculated from a 3-day food diary. The percentage of dietary intakes falling below 2/3 1980 Recommended Dietary Allowance (RDA) was comparable for users and non-users of supplements. Use of supplements markedly decreased the proportion of subjects with inadequate nutrient intake (using a 2/3 RDA criterion), particularly for vitamins B6, B12, and D, folic acid, and calcium. However, for both males and females, potentially excessive intake levels (10 times the RDA) of thiamin, vitamin A, and vitamin E supplementation were observed.

The adequacy of the protein intakes of elderly people without overt debilitating diseases was investigated on 691 free-living men and women divided into those aged 60-75 y and those greater than 75 y. In both age groups men and women had average protein intakes of 1.02-1.06 g/kg body weight, values well above the safe level of 0.75 g/kg recommended in a WHO/FAO/UNU report. Although plasma concentrations of albumin, prealbumin, and transferrin declined with age, these were not related to low intakes of protein by individual elderly people. Similarly, upper-arm muscle mass was not less in those elderly people at the lower end of the range of protein intakes. Thus in this population of overtly healthy elderly men and women, there was no evidence of protein deficiency in contrast to other surveys where elderly people with chronic diseases were included.