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3269. Worth knowing your onions?
Natural products
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NATURAL PRODUCTS 3269. Worth knowing your onions? Baghurst, K. I., Raj, M. J. & Truswell, A. S. (1977). Onions and platelet aggregation. Lancet I, 101. A small-scale study of members of the Jain community in India has suggested that the consumption of onions may have some protective function by affecting factors concerned in atherogenesis (Cited in F.C.T. 1977, 15, 493). Animal studies have indicated that onion or garlic tends to increase fibrinolysis in cholesterol-fed rabbits (ibid 1976, 14, 651). A small-scale experiment is now reported in which four men and five women aged from 23 to 40 yr were given in succession a control low-fat meal of 1000 kcal (4-2M J), a high-fat meal of 2000kcal (8-4M J) containing 160 g saturated fat, and the same high-fat meal to which was added 75 g fried onions. These meals were taken at weekly intervals after an overnight fast. Blood specimens taken before the meal and 2.5 hr after it showed that the highZfat meal produced a significantly greater rate of platelet aggregation than the control meal, but the high-fat meal supplemented with onions did not differ significantly from the control in this respect. The extent of platelet aggregation, however, was not significantly different from the control value after a high-fat meal taken with or without onions. Plasma triglyceride concentrations were significantly higher after each of the two high-fat meals than after the control meal. There was a slight indication of an increased fibrinolysis rate after the onionsupplemented meal, but there was such a wide scatter of individual values that this effect could not be regarded as statistically significant. No differences in blood-glucose concentration or thrombin clotting time appeared. [The scale of this study renders it of limited value. We are left, moreover, with an equivocal impression that onions may or may not help to avert atherosclerosis.]
3270. New fight on alcohol withdrawal Wood, J. & Laverty, R. (1976). Alcohol withdrawal syndrome following prolonged t-butanol administration to rats. Proc. Univ. Otago reed. Sch. 54, 86. The place of acetaldehyde in the metabolic system dealing with ethanol in chronic alcoholics and others is uncertain (Cited in F.C.T. 1976, 14, 220). The possibility that acetaldehyde is concerned in the withdrawal syndrome of alcoholics is discounted in this paper by Wood & Laverty. Rats were fed a liquid diet containing either 90 ml ethanol/litre or 20ml tert-butanol/litre for 21 days. When administration of the respective alcohols ceased, withdrawal signs appeared, after 2--4 hr in the case of ethanol and after 4-6 hr in the case of tertbutanol. Reactions to tert-butanol withdrawal were similar in nature to those seen after ethanol withdrawal but were more severe, four of five animals showing forepaw convulsions and all five suffering audiogenic convulsions in response to rattling keys.
Three animals died after tert-butanol was withdrawn, and all were irritable and aggressive for up to 72 hr. Although there were differences in the delay before onset of withdrawal signs and in their severity, the close resemblance between the withtlrawal syndrome of the two alcohols indicates that acetaldehyde, which cannot be formed metabolically from tert-butanol, is. not responsible for them, in rats at least.
3271. Beer drinking and colorectal cancer Enstrom, J. E. (1977). Colorectal cancer and beer drinking. Br. J. Cancer 35, 674. The incidence of colonic cancer is linked with the degree of westernization of the diet, and factors such as a lack of dietary fibre and high intakes of protein and fat have been implicated in its cause (Cited in F.C.T. 1976, 14, 210). Another aetiological factor may be beer drinking, which was strongly correlated with the incidence of both colonic and rectal cancer in a survey of 41 American States (Breslow & Enstrom, J. natn. Cancer Inst. 1974, 53, 631). The latest study includes d7 of the 51 American States (the other four having been omitted because of insufficient data or heavy alcohol consumption by transient non-residents). The cancer sites involved were: oesophagus, stomach, colon, rectum (colorectal), lung, breast and prostate. When correlation coefficients were calculated between 1960 beer consumption and the 1950-67 average age-adjusted white mortality rates from cancer at various sites, the strongest correlations that emerged (r = 0'81) were with rectal cancer in males and breast cancer in females. A high correlation was also found with rectal cancer in females, colonic and stomach cancer in both sexes (.particularly males) and oesophageal cancer in males. The correlations with rectal, colonic and breast cancer appeared to be even stronger when average annual beer consumption over the years 1941-60 was used in place of the 1960 consumption figures. Beer consumption was also strongly correlated with the ratio of male to female cancer of the rectum, and to a lesser extent of the oesophagus and colon, reflecting the greater consumption of beer by men. When the average annual change in beer consumption between 1945 and 1960 was compared with the average annual changes in death rates for 1950--67, again the strongest correlation emerged with rectal cancer. No allowance was made for a latent period between beer consumption and cancer development (the prohibition of alcohol between 1920 and 1933 being notable in this connexion) as the available data did not permit such analysis. The only other dietary factor which was as highly correlated with colonic and rectal cancer mortality rates as beer consumption was the per capita annual consumption of total absolute alcohol. Lesser correlations were demonstrated with the per capita consumption of spirits, fluid milk, cigarettes and wine, but the correlation with beef and fat intakes was very low, in conflict with international findings. Colorectal cancer was also correlated with population den-
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NATURAL PRODUCTS 3269. Worth knowing your onions? Baghurst, K. I., Raj, M. J. & Truswell, A. S. (1977). Onions and platelet aggregation. Lancet I, 101. A small-scale study of members of the Jain community in India has suggested that the consumption of onions may have some protective function by affecting factors concerned in atherogenesis (Cited in F.C.T. 1977, 15, 493). Animal studies have indicated that onion or garlic tends to increase fibrinolysis in cholesterol-fed rabbits (ibid 1976, 14, 651). A small-scale experiment is now reported in which four men and five women aged from 23 to 40 yr were given in succession a control low-fat meal of 1000 kcal (4-2M J), a high-fat meal of 2000kcal (8-4M J) containing 160 g saturated fat, and the same high-fat meal to which was added 75 g fried onions. These meals were taken at weekly intervals after an overnight fast. Blood specimens taken before the meal and 2.5 hr after it showed that the highZfat meal produced a significantly greater rate of platelet aggregation than the control meal, but the high-fat meal supplemented with onions did not differ significantly from the control in this respect. The extent of platelet aggregation, however, was not significantly different from the control value after a high-fat meal taken with or without onions. Plasma triglyceride concentrations were significantly higher after each of the two high-fat meals than after the control meal. There was a slight indication of an increased fibrinolysis rate after the onionsupplemented meal, but there was such a wide scatter of individual values that this effect could not be regarded as statistically significant. No differences in blood-glucose concentration or thrombin clotting time appeared. [The scale of this study renders it of limited value. We are left, moreover, with an equivocal impression that onions may or may not help to avert atherosclerosis.]
3270. New fight on alcohol withdrawal Wood, J. & Laverty, R. (1976). Alcohol withdrawal syndrome following prolonged t-butanol administration to rats. Proc. Univ. Otago reed. Sch. 54, 86. The place of acetaldehyde in the metabolic system dealing with ethanol in chronic alcoholics and others is uncertain (Cited in F.C.T. 1976, 14, 220). The possibility that acetaldehyde is concerned in the withdrawal syndrome of alcoholics is discounted in this paper by Wood & Laverty. Rats were fed a liquid diet containing either 90 ml ethanol/litre or 20ml tert-butanol/litre for 21 days. When administration of the respective alcohols ceased, withdrawal signs appeared, after 2--4 hr in the case of ethanol and after 4-6 hr in the case of tertbutanol. Reactions to tert-butanol withdrawal were similar in nature to those seen after ethanol withdrawal but were more severe, four of five animals showing forepaw convulsions and all five suffering audiogenic convulsions in response to rattling keys.
Three animals died after tert-butanol was withdrawn, and all were irritable and aggressive for up to 72 hr. Although there were differences in the delay before onset of withdrawal signs and in their severity, the close resemblance between the withtlrawal syndrome of the two alcohols indicates that acetaldehyde, which cannot be formed metabolically from tert-butanol, is. not responsible for them, in rats at least.
3271. Beer drinking and colorectal cancer Enstrom, J. E. (1977). Colorectal cancer and beer drinking. Br. J. Cancer 35, 674. The incidence of colonic cancer is linked with the degree of westernization of the diet, and factors such as a lack of dietary fibre and high intakes of protein and fat have been implicated in its cause (Cited in F.C.T. 1976, 14, 210). Another aetiological factor may be beer drinking, which was strongly correlated with the incidence of both colonic and rectal cancer in a survey of 41 American States (Breslow & Enstrom, J. natn. Cancer Inst. 1974, 53, 631). The latest study includes d7 of the 51 American States (the other four having been omitted because of insufficient data or heavy alcohol consumption by transient non-residents). The cancer sites involved were: oesophagus, stomach, colon, rectum (colorectal), lung, breast and prostate. When correlation coefficients were calculated between 1960 beer consumption and the 1950-67 average age-adjusted white mortality rates from cancer at various sites, the strongest correlations that emerged (r = 0'81) were with rectal cancer in males and breast cancer in females. A high correlation was also found with rectal cancer in females, colonic and stomach cancer in both sexes (.particularly males) and oesophageal cancer in males. The correlations with rectal, colonic and breast cancer appeared to be even stronger when average annual beer consumption over the years 1941-60 was used in place of the 1960 consumption figures. Beer consumption was also strongly correlated with the ratio of male to female cancer of the rectum, and to a lesser extent of the oesophagus and colon, reflecting the greater consumption of beer by men. When the average annual change in beer consumption between 1945 and 1960 was compared with the average annual changes in death rates for 1950--67, again the strongest correlation emerged with rectal cancer. No allowance was made for a latent period between beer consumption and cancer development (the prohibition of alcohol between 1920 and 1933 being notable in this connexion) as the available data did not permit such analysis. The only other dietary factor which was as highly correlated with colonic and rectal cancer mortality rates as beer consumption was the per capita annual consumption of total absolute alcohol. Lesser correlations were demonstrated with the per capita consumption of spirits, fluid milk, cigarettes and wine, but the correlation with beef and fat intakes was very low, in conflict with international findings. Colorectal cancer was also correlated with population den-