Aging and Diet

Relative risk of highest versus lowest flavonoid intake group, adjusted for age, diet and other risk factors for coronary heart disease. (C.I. = confidence interval)... 

Normal levels of serum cholesterol vary widely. For males, total cholesterol is in the range 130 to 320 mg/100 mL and HDL cholesterol ranges from 30 to 70 mg/100 mL. For females, the corresponding ranges are 130 to 295 and 35 to 80 mg/100 mL, respectively. Cholesterol levels depend on such factors as sex, age, diet, and emotional stress. Typical ranges at various age intervals are shown in Table El 1.1. 

Vadas, R.L., Burrows, M.T., and Hughes, R.N., Foraging strategies of dogwhelks, Nucella lapillus (L.) interacting effects of age, diet and chemical cues to the threat of predation, Oecologia, 100, 439, 1994. 

Although some sex-specific differences have been observed, the mechanism by which this occurs is unknown. These differences could be a result of differences in sex steroid levels as seen with the rat, but proof in humans is lacking. Basically, because of the confounding effects of age, diet, and physiological factors, interpretation of the sex-dependent differences in drug pharmacokinetics in humans is very complex and the role of metabolism remains to be clarified. 

Ben-David M, Dueey LK, Blundell GM and Bowyer RT (2001) Natural exposure of coastal river otters to mercury relation to age, diet, and survival. Environ Toxicol Chem 20 1986-1992. 

Similarly, approximately 500 to 600 g of phosphate are present, 85% of which Is found in the bone. The normal plasma concentration of calcium Is approximately 4.5 to 5.7 mEq/L, 50% of which Is protein bound. The remainder of the calcium is either complexed to corresponding counterions (46%) or exists in its ionized form (4%). It Is only the ionized form of calcium that is tightly hormonally regulated (varies less than 5-10%) (1,2). Because serum calcium concentrations fluctuate, so do the plasma levels of the hormones associated with calcium homeostasis. Serum phosphorous levels vary with age, diet, and hormonal status. The most common... 

In rodents taken as animal models, the cholesterol pool of adipose tissue is present in unesterified form and localized to the bulk triglyceride storage droplets. The cholesterol content increases with age, diet, and state of obesity. 

A smaller number of individuals, 132 samples, was analyzed for stable isotopes of nitrogen. There were two objectives to the nitrogen isotope analysis 1) to determine the amount of animal protein in the diet and to look for variation between the sexes and 2) to determine when infants were weaned from the breast. These objectives were addressed by selecting at least ten individuals, when available, from a number of age classes. Figure 1.1 illustrates the age distribution of the sample. Table 1.3 shows the results of these analyses. Individual 5 N values are provided in Herring et al. (1998). 

Figure 12.1. Relationship between collagen 8 N values and age of male and female rats raised on controlled diets, and sacrificed at 40 day intervals beginning 91 days after birth.

The mean difference between collagen and flesh (A Nco.f) values for the first sacrificed pairs (91 days after birth) is 0.3 1.09%o while that for third pairs (171 days after birth) is 1.4 0.45%o. This result was unanticipated but seems robust. This indicates the relationship between diet and tissue 8 N and age is complex and varies between tissues. Future studies of diet-tissue nitrogen isotope spacing will have to consider age effects. This contrasts with carbon isotopes (Ambrose and Norr 1993), where we have observed little increase in 8 C with age in the same individuals. 

This is not really a treatment but there is a view that glial cells can protect against seizures since the enzyme systems they possess (e.g. Na-K+ATPase and carbonic anhydrase) facilitate the regulation of ion movements and reduce the spread of seizures. Certainly ageing, a fatty diet, and phenytoin itself increase glial cell count while decreasing seizure susceptibility. In fact inhibition of carbonic anhydrase and the production of bicarbonate was one of the first treatments for epilepsy and a recent discovery that under certain circumstances intracellular bicarbonate can depolarise neurons has created a fresh interest in it. 

Pesticides have a statistically reliable effect on children in zones where OCPs are intensively used (in the Salyansk region of Azerbaijan, the amount of OCPs introduced into humans exceeded public health standards by up to 7.7 times). Primary illness of the endocrine system increased 3.1 times in children up to age 15 (over a five year observation period) in disruptions in diet and metabolism, the nervous system, and the sensory and respiratory organs in increased frequency of illness (over five years) in children up to age 15 (an overall increase by 3.6 times, and by class of illness, from 2.2-7.6 times) in the prevalence of pathological disruptions according to data from medical examinations of children from 8-14 years (an overall increase by 2.3 times, and by class of illness by 2.0-8.4 times) in... 

Mares-Perlman, JA, Fisher, AI, Klein, R, Block, G, Millen, AE, and Wright, JD, 2001. Lutein and zeaxanthin in the diet and serum and their relation to age-related maculopathy in the Third National Health and Nutrition Examination Survey. Am J Epidemiol 153, 424-432. 

Henderson L, Gregory J and Irving K (2003) The National Diet and Nutrition Survey Adults Aged 19 to 64 Years. Energy, protein, carbohydrate, fat and alcohol intake. The Stationery Office, London. 

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