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A symposium, Food Fights: Deciding about Diet and Disease, was held in Virginia in April, 1990. Scientific data indicate links between diet and disease, many of which have been identified from long-term epidemiological studies. Risk factors identified by such studies are only rough indicators for a group, not for an individual's risk. Another aspect, that of ethics and decision-making, was brought up in reference to epidemiological studies. These studies, less precise than rigidly controlled laboratory studies, do not allow the same firm conclusions, and the ways in which data from these studies are accepted or rejected will affect the resulting conclusions and policies. The food industry frequently tends to resort to a double-pronged type of advertising, as exemplified by the current practice of associating certain food products with gains in health or fitness, while alluding to memories of good food and home cooking for other foods. Multiple health claims by food advertisers combined with indefinite scientific conclusions lead to worse confusion among consumers. It is often the consumer advocate who counters industrial claims and spurs the government to action. Appropriate food labels are the key to protecting and informing the consumer. Organizations such as the American Heart Association (AHA) also claim a role in promoting better health and educating the public, and the AHA has recently focused on the food label as a critical point for influencing dietary choice. The Food and Drug Administration (FDA) is currently working on guidelines as to which claims may be made, and the food labeling format is also to be revised. The forum participants agreed that epidemiological methodologies need improvement, particularly so that long-term studies can be performed without the need for short-term demonstrable results. However, they disagreed as to whether current research findings are adequate to justify strong changes in public policy. The audience wanted more information about estimation of personal risk, especially for women and children, and for identification of predisposing genetic factors. They also wanted to know the tradeoffs involved with dietary modification, so that they could make their own informed decisions about life style changes. (Consumer Summary produced by Reliance Medical Information, Inc.)

A study was undertaken to determine the effect of varying periods of undernutrition in postnatal life on the size and chemical composition of the brain in rehabilitated adult animals. Four groups of male albino rats were drawn from litters of 16 pups nursed by an undernourished dam. One group was weaned at 3 weeks to a diet of 18% casein. Three similar groups were fed a 3% protein diet until 5, 7 and 9 weeks of age. A diet of 18% protein was then fed until the rats were 19 weeks old. The growth, and brain size and composition of these nutritionally deprived groups were compared with those of littermates adequately nourished from birth. Undernutrition during suckling caused a degree of stunting of body size that was only partially reversed by nutritional rehabilitation. Brain size and brain DNA were depressed by undernutrition in the preweaning period but were not affected further by deprivation in the post-weaning period. They did not respond to an adequate diet. Brain size was less affected than total body size. Cholesterol levels of brain were significantly and irreversibly depressed if undernutrition occurred through 5 weeks of age but responded to earlier rehabilitation. Phospholipid phosphorus and RNA content of brain were similar in all groups. The chemical composition of the smaller brains of the deprived animals was not significantly different on the basis of percentage composition than that of the larger brains of the well-nourished animals.

Reproductive performance and certain aspects of maternal biochemical response were studied in female rats of the Wistar strain maintained with a basal diet containing either an adequate or a low level of thiamine from weaning until mating. During pregnancy the rats were fed an adequate basal diet, or the same basal diet with all vitamin levels doubled. Fewer young were produced by animals fed at the low level of thiamine prior to pregnancy. Albumin and γ-globulin were the only serum proteins that appeared to be influenced by thiamine intake. In other respects reproductive performance and maternal biochemical response were normal even when food intake and thiamine level were low prior to pregnancy. The young were of normal weight. Total serum protein, hemoglobin and hematocrit were similar. Doubling the intake of thiamine and other vitamins during pregnancy had no effect on reproductive performance. Thiamine content in the young and in livers of mothers was related to thiamine intake during pregnancy and was not influenced by low thiamine level prior to pregnancy.

A dietary survey of 18 villages and 1 urban site was carried out in Nepal using the 24-hr recall method to obtain household food consumption. The diet of the Nepalese people is clearly superior to many other areas of the Far East but is generally lacking in sufficient high quality protein, calcium, vitamin A, riboflavin, and ascorbic acid. Iron, thiamine, and niacin intakes are adequate to high due to consumption of large amounts of unmilled rice. Although the clinical nutritional status of the population is generally satisfactory, the high mortality rate among children under five suggests that marginal malnutrition exists, which, coupled with constant exposure to a contaminated environment, is a major factor implicated in child deaths in Nepal.

Weekly changes in the concentration of total protein of the plasma, in hemoglobin and in hematocrit were observed in control and vitamin B6-deficient pregnant and non-pregnant rats.

Eight anthropometric measurements were made on 281 2- and 3-year-old children in the city of Honolulu. Males were significantly heavier than females of the same age; males were also significantly longer in total body measurements. Significant differences between sexes were not observed, however, in trunk length, midupper arm circumference, and arm diameter-not-fat. Part-Hawaiian children had significantly longer bodies than Japanese children but differences in trunk length, midupper arm circumference, and weight were not significant. There were no significant anthropometric differences between low and middle income groups, both of which are relatively low in comparison with the cost of living in Hawaii. No statistically significant differences in skin-fold thicknesses were observed between age categories, low and middle income groups, or ethnic groups. Differences of borderline significance (5% level) between males and females were observed only on the subscapular skin-fold measurements. British standards were used to evaluate triceps and subscapular skinfold thicknesses.Although it is impossible to positively diagnose degree of fatness for individuals from measures of heights and weights alone, in reasonably well-nourished populations, the weight-for-height classification may provide an adequate screening device.On the basis of skin-fold definitions and weight-for-height classifications, approximately three-fourths of the Honolulu children appear to be normal, whereas 10–20% might be considered lean and another 5-10% might be considered fat.

Diets of low-income preschool children tended to be lower in calcium, vitamin A, and ascorbic acid than those of children from middle-income families, although biochemical and clinical data for both groups were, in general, similar. Iron intakes for all children were low in comparison with present recommended levels. Low- and middle-income Honolulu children tended to be short for their age in comparison with Mainland height standards.

Food intakes of nearly all of fifty-two infants, two to nine months of age, met at least two-thirds of the recommended allowances for nutrients except for iron. Sodium intakes were, for the most part, above the requirement for growth and for some infants approached or exceeded suggested maximum levels. The possible relationship of sodium intake in infancy to hypertension in later life is discussed.

Reproductive performance and tissue lipid composition were studied in Sprague Dawley strain female rats fed from weaning diets containing 5% of corn oil, olive oil or HVO or 15% HVO, and deprived of vitamin B6a minimum of three weeks prior to mating.

The effects of two types of fat, corn oil and a hydrogenated shortening, at 15% dietary levels, have been determined in studies of reproductive performance and body composition in vitamin B6-deficient and control female rats, when the deficiency was initiated at 80 days of age, at least three weeks prior to mating.

Changes in blood volume, hemoglobin and serum protein have been investigated in deoxypyridoxine-fed pregnant and non-pregnant rats and in control rats fed pyridoxine under similar conditions.

Changes in blood pressure and thiocyanate space have been investigated in pregnant and nonpregnant vitamin B6-deficient and control rats.

Reproductive performance, serum proteins and hematological response were studied in female rats of the Wistar strain, maintained from weaning until mating with a diet containing either an adequate or a low level of thiamine. During gestation the rats were fed an adequate diet or the same diet containing one-tenth the level of thiamine. Food intake and weight gain were markedly influenced by diet during pregnancy. In animals fed the low level of thiamine during pregnancy, prepregnancy diet also influenced food intake and maternal weight gain. Heavier young were produced by animals fed adequate thiamine during pregnancy but fetal weight was not affected by prepregnancy diet. Total serum protein was similar for all groups although γ-globulin concentration were lower in animals fed adequate thiamine during pregnancy. Hemoglobin and hematocrit values indicated the expected hemodilution of pregnancy in animals fed adequate thiamine and apparent hemoconcentration in animals fed the low thiamine diet. Thiamine content in the young and livers of mothers were related to thiamine intake during pregnancy and were not significantly influenced by prepregnancy diet.

Hearts of rats maintained on a thiamine-free diet were found to develop a resistance to the necrogenic effects of massive doses of isoproterenol within 2 to 3 weeks following initiation of the dietary regime. Feeding thiamine for 5 days to the deficient animals did not diminish the acquired resistance to the necrotic effects of isoproterenol.

This comprehensive handbook is geared primarily to physicians involved in infant and child health care, in recognition that most medical schools and hospital teaching centers give insufficient attention to nutrition as an integral part of health care. There are 38 chapters, covering basic nutrition, assessment of nutritional status, nutritional needs and feeding of infants and young children, availability of community nutrition services and food assistance programs, and clinical applications. The last section covers a wide variety of common clinical problems, as well as some that are relatively rare. Finally, there are several chapters grouped as "Miscellaneous Topics." This section includes nutritional aspects of vegetarianism, health foods and fad diets, megavitamin therapy, nutrition and athletic performance, and food additives. Included also are chapters on infection, immune mechanisms, and the relationship between iron nutritional status and incidence of infection in infancy (which might just as well have been incorporated into the section