Biomedical subjects

I B King

Publications and source records attributed to I B King.

17 recordsLinked to original sources

PubMed2001

The association of fatty acids with prostate cancer risk.

BACKGROUND: Animal studies indicate that omega-6 fatty acids promote and omega-3 fatty acids inhibit tumor development. This pilot study was designed to evaluate whether these fatty acids are associated with human prostate cancer. METHODS: Levels of erythrocyte membrane omega-3 and omega-6 fatty acids were determined for 67 incident prostate cancer cases and 156 population-based controls. RESULTS: Prostate cancer risk was increased in the highest compared to the lowest quartile of alpha-linolenic acid (OR = 2.6, 95% CI = 1.1-5.8, trend P = 0.01). Positive associations were also observed with higher levels of linoleic acid (OR = 2.1, 95% CI = 0.9-4.8) and total omega-6 fatty acids (OR = 2.3, 95% CI = 1.0-5.4). CONCLUSIONS: Results are consistent with other studies showing that linoleic and total omega-6 fatty acids increase risk of prostate cancer. Contrary to animal studies, alpha-linolenic acid was also positively associated with risk. Further research will be required to clarify the role of these fatty acids in human prostate cancer.

Adenocarcinoma↗

PubMed2001

Plasma concentrations of carotenoids, retinol, and tocopherols in preeclamptic and normotensive pregnant women.

This case-control study was conducted in Lima, Peru, from June 1997 through January 1998 to assess whether plasma concentrations of carotenoids (alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin, beta-cryptoxanthin), retinol, and tocopherols (alpha-tocopherol and gamma-tocopherol) are decreased in women with preeclampsia. A total of 125 pregnant women with preeclampsia and 179 normotensive pregnant women were included. Plasma concentrations of antioxidants were determined using high performance liquid chromatography. After adjusting for maternal demographic, behavioral, and reproductive characteristics and total plasma lipid concentrations, the authors found a linear increase in risk of preeclampsia with increasing concentrations of alpha-tocopherol (odds ratio of the highest quartile = 3.13; 95% confidence interval: 1.06, 9.23, with the lowest quartile as the reference group; p value of the test of linear trend = 0.040). The risk of preeclampsia decreased across increasing quartiles of concentrations for retinol (odds ratio of the highest quartile = 0.32; 95% confidence interval: 0.15, 0.69, with the lowest quartile as the reference group; p value of the test of linear trend = 0.001). Some of these results are inconsistent with the prevailing hypothesis that preeclampsia is an antioxidant-deficient state. Preliminary findings confirm an earlier observation of increased plasma concentrations of alpha-tocopherol among women with preeclampsia as compared with normotensive pregnant women.

Adolescent↗

PubMed2000

Methylenetetrahydrofolate reductase 677 C --> T polymorphism, plasma folate, vitamin B(12) concentrations, and risk of preeclampsia among black African women from Zimbabwe.

We conducted a case control study at Harare Maternity Hospital, Zimbabwe. We genotyped a total of 171 cases with preeclampsia or eclampsia and 185 normotensive control subjects for the methylenetetrahydrofolate reductase (MTHFR) 677 C --> T genotype. The wild-type allele frequency among cases and controls was 91.2 and 91.3%, respectively. Only one subject (0.3%) was homozygous for the 677 C --> T MTHFR genotype and this subject had preeclampsia. After adjustment for confounding factors, there was statistically no significant association between maternal MTHFR genotype and risk of preeclampsia (adjusted odds ratio = 1.0; 95% CI, 0.5-1.9). In addition, plasma homocyst(e)ine, vitamin B(12), and folate concentrations were not statistically different between normotensive control subjects with wild-type genotype as compared with normotensive subjects who were heterozygous for the mutant allele. Conversely, there was a strong graded association between maternal plasma folate concentration and risk of preeclampsia. Women with plasma folate concentrations less than 5.7 nmol/L experienced a 10. 4-fold increase in risk of preeclampsia. There was no clear pattern of preeclampsia risk and vitamin B(12) concentrations.

Adolescent↗

PubMed2000

Leukocyte selenium, zinc, and copper concentrations in preeclamptic and normotensive pregnant women.

Preeclampsia is an important cause of maternal and perinatal mortality worldwide. The etiology of this relatively common medical complication of pregnancy, however, remains unknown. We studied the relationship between maternal leukocyte selenium, zinc, and copper concentrations and the risk of preeclampsia in a large hospital-based case-control study. One hundred seventy-one women with proteinuric pregnancy-induced hypertension (with or without seizures) comprised the case group. Controls were 184 normotensive pregnant women. Leukocytes were separated from blood samples collected during the patients' postpartum labor and delivery admission. Leukocyte concentrations for the three cations were measured by inductively coupled plasma-mass spectrometry (ICP-MS). Concentrations for each cation were reported as micrograms per gram of total protein. Women with preeclampsia had significantly higher median leukocyte selenium concentrations than normotensive controls (3.23 vs 2.80 microg/g total protein, p < 0.0001). Median leukocyte zinc concentrations were 31% higher in preeclamptics as compared with controls (179.15 vs 136.44 microg/g total protein, p < 0.0001). Although median leukocyte copper concentrations were slightly higher for cases than controls, this difference did not reach statistical significance (17.72 vs 17.00 microg/g total protein, p = 0.468). There was evidence of a linear increase in risk of preeclampsia with increasing concentrations of selenium and zinc. The relative risk for preeclampsia was 3.38 (adjusted odds ratio [OR] = 3.38, 95% confidence interval [CI] = 1.53-7.54) among women in the highest quartile of the control selenium distribution compared with women in the lowest quartile. The corresponding relative risk and 95% CI for preeclampsia was 5.30 (2.45-11.44) for women in the highest quartile of the control zinc distribution compared with women in the lowest quartile. There was no clear pattern of a linear trend in risk with increasing concentration of leukocyte copper concentrations (adjusted for linear trend in risk = 0.299). Our results are consistent with some previous reports. Prospective studies are needed to determine whether observed alterations in selenium and zinc concentrations precede preeclampsia or whether the differences may be attributed to preeclampsia-related alterations in maternal and fetal-placental trace metal metabolism.

Adult↗

PubMed2000

Brassica vegetables increase and apiaceous vegetables decrease cytochrome P450 1A2 activity in humans: changes in caffeine metabolite ratios in response to controlled vegetable diets.

Induction or inhibition of biotransformation enzymes, enzymes that activate or detoxify numerous xenobiotics, is one mechanism by which vegetables may alter cancer risk. Using a randomized crossover design, we examined the effect of various vegetable diets on cytochrome P450 (CYP) 1A2, N-acetyltransferase 2 (NAT2) and xanthine oxidase activity in humans. Men and women, non-smokers, on no medication and 20-40 years of age ate four 6-day controlled diets: basal (vegetable-free) and basal with three botanically defined vegetable groups. Enzyme activities were determined by measuring urinary caffeine metabolite ratios after a 200 mg caffeine dose on the last day of each feeding period. Mean CYP1A2 activity for 19 men and 17 women (least squares means adjusted for sex, GSTM1 genotype, urine volume and feeding period) with basal, brassica, allium and apiaceous vegetable diets differed significantly (P </=ISOdia</= 0. 0005) by diet, irrespective of the caffeine metabolite molar ratio used to describe CYP1A2 activity; brassica vegetables increased (P <0.04) and apiaceous vegetables decreased (P </=ISOdia</= 0.02) activity compared with the basal and allium diets. There was no effect of diet on NAT2 and xanthine oxidase activities and none of the subjects differed by GSTM1 genotype. These results demonstrate that while one vegetable subgroup induces human CYP1A2 activity, another subgroup inhibits it. This points to a complex association between consumption of a typical diet of various vegetables and biotransformation enzyme activities in humans, an association that may be difficult to interpret in observational studies.

Adult↗

PubMed1999

Study of diet, biomarkers and cancer risk in the United States, China and Costa Rica.

One striking paradox in epidemiologic research is the strong association between diet and cancer in ecologic studies compared with the weaker associations reported in many within-country case-control and cohort studies. However, most ecologic studies have relied on indirect measures of dietary intake, such as food disappearance data. The objectives of our study were to assess the feasibility of collecting dietary and biomarker data from individuals living in countries having markedly different dietary patterns and cultures and to examine the magnitude of the between-country variation in their measurement. Adults surveyed in Shanghai (China), Costa Rica and King County (Washington, USA) completed a 24-hr dietary recall, a cancer risk factor survey, and provided a blood sample. We analyzed a subset of the blood specimens for vitamins C, E, carotenoids and phospholipid fatty acids. We observed substantial differences in nutrient intakes and in mean plasma concentrations of dietary biomarkers across the study populations. For example, King County participants had the highest daily intake of vitamin C (mean 78.3 +/- 12.2 mg compared with 42.6 +/- 38.3 mg in Shanghai and 34.8 +/- 43.8 mg in Costa Rica). The mean plasma vitamin C level in King County was also the highest of the 3 study sites: 927.9 +/- 43.9 microg/dl in King County, 585.7 +/- 35.9 microg/dl in Shanghai and 461.1 +/- 33.1 microg/dl in Costa Rica. Plasma trans fatty acids (a biomarker of a diet high in hydrogenated fats) were highest in King County and lowest in Shanghai.

Adult↗

PubMed1999

Maternal second trimester serum tumor necrosis factor-alpha-soluble receptor p55 (sTNFp55) and subsequent risk of preeclampsia.

Preeclampsia is characterized by diffuse vascular endothelial dysfunction. Tumor necrosis factor-alpha (TNF-alpha), which plays a key role in the cytokine network responsible for immunoregulation, is also known to contribute to endothelial dysfunction and other metabolic disturbances noted in preeclampsia. Results from cross-sectional studies and one longitudinal study indicate that TNF-alpha (or its soluble receptor, sTNFp55) is increased in the peripheral circulation and amniotic fluid of women with preeclampsia as compared with normotensive women. Between December 1993 and August 1994, prediagnostic sTNFp55 concentrations (a marker of excessive TNF-alpha release) were measured in 35 women with preeclampsia and 222 normotensive women to determine whether elevations precede the clinical manifestation of the disorder. Logistic regression procedures were used to calculate maximum likelihood estimates of odds ratios and 95% confidence intervals. Mean second trimester (15-22 weeks' gestation) serum sTNFp55 concentrations, measured by enzyme-linked immunosorbent assay, were 14.4% higher in preeclamptic women than in normotensive controls (716.6 pg/ml (standard deviation 193.6) vs. 626.4 pg/ml (standard deviation 158.0); p = 0.003). The relative risk of preeclampsia increased across successively higher quintiles of sTNFp55 (odds ratios were 1.0, 1.3, 2.1, and 3.7, with the lowest quintile used as the referent; p for trend = 0.007). After adjustment for maternal age, adiposity, and parity, the relative risk between extreme quintiles was 3.3 (95% confidence interval 0.8-13.4). These findings indicate that the level of TNF-alpha in maternal circulation is increased prior to the clinical manifestation of the disorder, and they are consistent with the hypothesized role of cytokines in mediating endothelial dysfunction and the pathogenesis of preeclampsia. Further work is needed to identify modifiable risk factors for the excessive synthesis and release of TNF-alpha in pregnancy, and to assess whether lowering of TNF-alpha concentrations in pregnancy alters the incidence and severity of preeclampsia.

Adolescent↗

PubMed1999

Plasma lipid concentrations in pre-eclamptic and normotensive Peruvian women.

OBJECTIVES: Dyslipidemia is thought to be of etiological importance in pre-eclampsia. We studied the relationship between maternal plasma lipid concentrations and risk of pre-eclampsia. METHODS: A total of 125 pre-eclampsia cases and 179 normotensive control subjects were included in this case-control study conducted in Lima, Peru, between August 1997 and January 1998. Postdiagnosis, antepartum plasma lipid profiles were determined by standard enzymatic methods. Logistic regression procedures were used to calculate odds ratios (OR) adjusted for potential confounders. RESULTS: Mean plasma total cholesterol and triglyceride concentrations were, on average, 6% and 21% higher in pre-eclamptics than controls, respectively. High-density lipoprotein (HDL) cholesterol concentrations were, on average, 9% lower in cases than controls. After adjusting for maternal age, prepregnancy body mass index, education, parity and other potential confounders, the risk of pre-eclampsia increased with successively higher quartiles of plasma triglyceride (adjusted OR: 1.00, 1.62, 2.21, 5.00, with the lowest quartile as referent; P-value for trend < 0.001). The association between pre-eclampsia risk and plasma total cholesterol was much less pronounced. In general, there was an inverse association between pre-eclampsia risk and HDL cholesterol concentration (adjusted OR: 1.00, 0.41, 0.50, 0.38, with the first quartile as the referent group; P-value for trend = 0.02). CONCLUSIONS: These findings suggest that high triglyceride and low HDL cholesterol concentrations are important risk factors for pre-eclampsia among Peruvian women.

Adult↗

PubMed1999

Pre-eclampsia disrupts the normal relationship between serum leptin concentrations and adiposity in pregnant women.

The adipocyte hormone, leptin, is secreted in proportion to adipose mass and is implicated in the regulation of energy balance via its central actions on food intake and sympathetic nervous system activity. The placenta was also shown recently to be a possible source of leptin in pregnant women, raising the possibility that the normal relationship between leptin and adiposity may be altered in pre-eclampsia. We therefore sought to assess the extent to which maternal second trimester serum leptin concentrations differed for women who would subsequently develop pre-eclampsia and those who would remain normotensive. This nested case-control study population comprised 38 women with pregnancy-induced hypertension and proteinuria (pre-eclampsia) and 192 normotensive women. Multiple least-squares regression procedures were used to assess the independent relationship between leptin concentrations and risk of pre-eclampsia. Serum leptin concentrations, measured by radioimmunoassay, were highly correlated with maternal pre-pregnancy and second trimester body mass index (r = 0.71 and r = 0.74 respectively; P < 0.001 for both) among normotensive women, and to a lesser extent among women who developed pre-eclampsia (r = 0.29 and r = 0.42; P = 0.09 and 0.02 respectively). Among women with a pre-pregnancy body mass index of < or = 25 kg/m2, pre-eclampsia cases compared with controls had higher mean second trimester leptin concentrations after adjustment for confounding factors. In contrast, pre-eclampsia cases had lower mean leptin concentrations than controls for those women with a pre-pregnancy body mass index above 25 kg/m2. Other factors in addition to the level of adiposity may therefore influence serum leptin concentrations in pre-eclamptic pregnant women. Our results suggest the possibility that leptin, like several other placentally derived substances (e.g. steroid hormones, eicosanoids and cytokines), may be involved in the pathogenesis of pre-eclampsia. Further work is needed to confirm our findings and to assess the metabolic importance and determinants of leptin concentrations in uncomplicated and pre-eclamptic pregnancies.

Adipose Tissue↗

PubMed1999

Elevated second-trimester serum homocyst(e)ine levels and subsequent risk of preeclampsia.

OBJECTIVE: Elevated plasma homocyst(e)ine is a risk factor for endothelial dysfunction and vascular disease. In late gestation, levels of homocyst(e)ine are higher in preeclamptics, as compared with normotensive pregnant women. Our objective was to determine whether homocyst(e)ine elevations precede the development of preeclampsia. STUDY DESIGN: We used a prospective nested case-control study design to compare second trimester maternal serum homocyst(e)ine concentrations in 52 patients who developed preeclampsia (pregnancy-induced hypertension with proteinuria) compared with 56 women who remained normotensive throughout pregnancy. Study subjects were selected from a base population of 3, 042 women who provided blood samples at an average gestational age of 16 weeks and later delivered at our center. Serum homocyst(e)ine was measured by high-performance liquid chromatography and electrochemical detection. RESULTS: Approximately 29% of preeclamptics, as compared to 13% of controls had homocyst(e)ine levels >/=5.5 micromol/l (upper decile of distribution of control values). Adjusted for maternal age, parity, and body mass-index, a second trimester elevation of homocyst(e)ine was associated with a 3. 2-fold increased risk of preeclampsia (adjusted OR = 3.2; 95% CI 1. 1-9.2; p = 0.030). There was evidence of a interaction between maternal adiposity (as indicated by her prepregnancy body mass index) and parity with second trimester elevations in serum homocyst(e)ine. Nulliparous women with elevated homocyst(e)ine levels experienced a 9.7-fold increased risk of preeclampsia as compared with multiparous women without homocyst(e)ine elevations (95% CI 2.1-14.1; p = 0.003). Women with a higher prepregnancy body mass index (>/=21.4 kg/m(2), or upper 50th percentile) and who also had elevated homocyst(e)ine levels, as compared with leaner women without homocyst(e)ine elevations were 6.9 times more likely to later develop preeclampsia (95% CI 1.4-32.1; p = 0.016). CONCLUSION: Our findings are consistent with other indications of vascular endothelial dysfunction predating clinical preeclampsia. Studies designed to examine the effect of dietary and/or pharmacological mediators of homocyst(e)ine metabolism in preeclampsia are warranted.

Adult↗

PubMed1998

Assessment of trans-fatty acid intake with a food frequency questionnaire and validation with adipose tissue levels of trans-fatty acids.

Past studies of the association of trans-fatty acid intake with coronary heart disease have been hindered by the lack of a database on the trans-fatty acid content of various foods. The authors used new data from the US Department of Agriculture to estimate trans-fatty acid intake using a self-administered food frequency questionnaire (FFQ), and they assessed the validity of the FFQ by comparing the dietary estimates with trans-fatty acid concentrations in adipose tissue. The 1996 study included 27 women and 24 men aged 51-78 years. The mean consumption of total trans-fatty acids estimated from the FFQ was 2.24 g per day and 5% of total dietary fat. The mean concentration of total trans-fatty acids in buttock adipose tissue was 4.7% of total fatty acids. Pearson correlations between total dietary intake of trans-fatty acids and total trans-fatty acid levels in adipose tissue were 0.67 (95% confidence interval (CI) 0.36-0.84) among men and 0.58 (95% CI 0.26-0.79) among women. After adjustment for energy intake, age, and body mass index, the correlation coefficients were 0.76 (95% CI 0.51-0.89) among men and 0.52 (95% CI 0.17-0.75) among women. The FFQ validated in this study is an important new tool for assessing usual intake of trans-fatty acids.

Adipose Tissue↗

PubMed1998

Plasma tumor necrosis factor-alpha soluble receptor p55 (sTNFp55) concentrations in eclamptic, preeclamptic and normotensive pregnant Zimbabwean women.

We sought to examine the relationship between excessive tumor necrosis factor-alpha (TNF-alpha) release (as measured by sTNFp55 plasma concentrations) and risk of eclampsia and preeclampsia, respectively, among sub-Saharan African women delivering at Harare Maternity Hospital, Zimbabwe. In total, 33 pregnant women with eclampsia, 138 women with preeclampsia and 185 normotensive women were included in a case-control study conducted during the period, June 1995 through April 1996. Postpartum plasma sTNFp55 was measured by enzyme linked immunosorbent assay. Women with eclampsia had significantly higher sTNFp55 than normotensive controls (1.87 vs 1.35 ng/ml, P<0.001). Similarly, women with preeclampsia had sTNFp55 concentrations higher than normotensive controls (1.69 vs 1.35 ng/ml, P < 0.001). The odds ratio for eclampsia was 5.00 (adjusted odds ratio (OR) 5.00, 95% confidence interval (CI) 1.20-20.92) among women in the highest quartile of the control sTNFp55 distribution compared with women in the lowest quartile. The corresponding odds ratio and 95% CI for preeclampsia was 2.37 (1.11-5.06). Postpartum plasma sTNFp55 concentrations are increased among Zimbabwean women with eclampsia and preeclampsia as compared with their normotensive counterparts. These findings are consistent with the hypothesized role of cytokines in mediating endothelial dysfunction and the pathogenesis of preeclampsia/eclampsia. Additional work is needed to identify modifiable risk factors for the excessive synthesis and release of TNF-alpha in pregnancy; and to assess whether measurements of sTNFp55 early in pregnancy may be used to identify women likely to benefit from anti-inflammatory therapy.

Antigens, CD↗

PubMed1998

Risk of preeclampsia in relation to elaidic acid (trans fatty acid) in maternal erythrocytes.

OBJECTIVE: Trans fatty acids, formed by the partial hydrogenation of vegetable oils, are associated with increases in plasma concentrations of cholesterol, triglyceride, lipoprotein (a), and coronary heart disease risk. Trans fatty acids may also increase platelet aggregation and alter eicosanoid biosynthesis. We studied the relation between maternal dietary intake of trans fatty acids and risk of preeclampsia. METHODS: Maternal intake of elaidic acid, one of the most abundant dietary trans fatty acids and other fatty acids were estimated using gas-liquid chromatography on erythrocytes from 22 women with preeclampsia and 40 normotensive controls. Fatty acids were expressed as the percentage of total fatty acids in erythrocytes. Logistic regression procedures were used to estimate odds ratios and 95% confidence intervals. RESULTS: Mean levels of elaidic acid were 28% higher among preeclamptics (0.43 +/- 0.12) as compared with controls (0.31 +/- 0.12; p < 0.001). After adjusting for confounding factors, women with the highest levels of elaidic acid (median = 0.47) were 7.4 times (odds ratio = 7.4; 95% confidence interval 1.4-39.7) more likely to have had their pregnancy complicated by preeclampsia as compared with those women with the lowest levels (median 0.24). Risk of preeclampsia appeared to increase with increasing levels of elaidic acid (p value for linear trend = 0.05). CONCLUSION: These cross-sectional data suggest that diets high in elaidic acid may be associated with an increased risk of preeclampsia. This hypothesis should be examined in larger longitudinal studies.

Cross-Sectional Studies↗

PubMed1997

Perspectives on integrating experimental and epidemiologic research on diet, anthropometry and breast cancer.

Three perspectives on the integration of experimental and epidemiologic research on diet, anthropometry and breast cancer are presented. 1) Although body weight and height have been linked to breast cancer risk by epidemiologic research, their roles have not been directly explored with animal models. However, basic, clinical and epidemiologic research on obesity and associated metabolic alterations may be pertinent. Individual differences in the timing and magnitude of weight gain and loss during adult life need to be considered in epidemiologic studies of adiposity and breast cancer, along with individual differences in the pattern of body fat deposition, the hormonal and metabolic changes that accompany the adiposity, and family history of obesity-related chronic diseases. Animal models with genetic predispositions to obesity, diabetes and breast cancer merit further exploration, as well as models that can evaluate exposures occurring after puberty. 2) The synergy between experimental and epidemiologic studies on fat and energy intake and breast carcinogenesis has been productive because each discipline has had to incorporate recent findings of the other. Dietary studies utilizing animals with different genetic profiles are promising, but require identification of the critical genes in human carcinogenesis. 3) Controlled dietary intervention studies with human participants using intermediate endpoints can bridge the gap between animal and epidemiologic studies, but generally accepted intermediate endpoints for breast cancer need to be developed. Such studies would permit better control of diet than large clinical trials and the opportunity to explore mechanisms.

Adult↗

PubMed1995

Omega-3 fatty acids in maternal erythrocytes and risk of preeclampsia.

Preeclampsia is a systemic disease characterized by diffuse endothelial dysfunction, increased peripheral vascular resistance, coagulation abnormalities, antioxidant deficiency, persistent elevations of maternal leukocyte-derived cytokines, and hyperlipidemia. Fish oil, rich in omega-3 polyunsaturated fatty acids, is known to reduce fasting and postprandial triglycerides and to decrease platelet and leukocyte reactivity; it may also decrease blood pressure. Additionally, omega-3 fatty acids may beneficially influence vessel wall characteristics and blood rheology. In light of the potential beneficial effects of dietary omega-3 fatty acids, we conducted a cross-sectional case-control study to examine the hypothesized exposure-effect relation between maternal dietary intake of marine omega-3 fatty acids and risk of preeclampsia. We measured polyunsaturated fatty acids in erythrocytes obtained from 22 preeclamptic women and 40 normotensive women; we measured polyunsaturated fatty acids as the percentage of total fatty acids from gas chromatography. We employed logistic regression procedures to estimate odds ratios (ORs) and 95% confidence intervals (CIs). After adjusting for confounders, women with the lowest levels of omega-3 fatty acids were 7.6 times more likely to have had their pregnancies complicated by preeclampsia as compared with those women with the highest levels of omega-3 fatty acids (95% CI = 1.4-40.6). A 15% increase in the ratio of omega-3 to omega-6 fatty acids was associated with a 46% reduction in risk of preeclampsia (OR = 0.54; 95% CI = 0.41-0.72). Low erythrocyte levels of omega-3 fatty acids and high levels of some omega-6 fatty acids, particularly arachidonic acid, appear to be associated with an increased risk of preeclampsia.

Adult↗

PubMed1990

Effects of shellfish consumption on lipoproteins in normolipidemic men.

Eighteen normolipidemic males were fed six different species of shellfish; each shellfish was fed so that protein in shellfish equalled that in animal foods in the normal diet, with less than one-half of the amount of fat in animal foods allowed for preparation of the shellfish. Oyster, clam, crab, and mussel diets, low in cholesterol and high in n-3 fatty acids, lowered VLDL triglycerides and cholesterol and, except for the mussel diet, LDL and total cholesterol. Squid and shrimp diets, higher in cholesterol and lower in n-3 fatty acids, did not change the blood lipids. The ratio of LDL to HDL cholesterol was decreased on the oyster and mussel diets. Oyster, mussel, and squid diets increased HDL2 cholesterol. Cholesterol absorption was decreased on the oyster, clam, and mussel diets. When consumed with moderate dietary fat restriction, oysters, clams, mussels, and crab appear to be useful in hypolipidemic diets for normolipidemic men.

Adult↗

PubMed1990

Divergent lipoprotein responses to fish oils with various ratios of eicosapentaenoic acid and docosahexaenoic acid.

To determine if the ratio of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids in fish oil had an effect on plasma lipid responses, we randomly fed eight normolipidemic men three 36%-fat diets containing primarily butter, EPA-rich pollock oil, or DHA-rich tuna or salmon-blend oils. Plasma EPA and DHA reflected the amounts in the diets. Compared with values for the butter diet, very-low-density lipoprotein (VLDL) triglycerides decreased equally (71-78%) with all diets; low-density lipoprotein (LDL) cholesterol (LDL-C) and apolipoprotein B decreased 26% and 13%, respectively, on the tuna and salmon-blend oil but did not change (-1%) and increased 19% with the pollock diet; high-density lipoprotein cholesterol (HDL-C) and lipoproteins A-I and A-II decreased with all diets but more with the pollock diet than with the tuna and salmon diets. The 23-31% decrease in total cholesterol on the tuna and salmon diets resulted mostly from decreased LDL-C whereas the 16% decrease on pollock oil resulted mostly from a decrease in HDL-C.

Butter↗