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Eggs distinctly modulate plasma carotenoid and lipoprotein subclasses in adult men following a carbohydrate-restricted diet. Mutungi G, Waters D, Ratliff J, Puglisi M, Clark RM, Volek JS, Fernandez ML. J Nutr Biochem. 2009 Apr 13. [Epub ahead of print] PMID: 19369056 We previously reported that carbohydrate restriction (CR) (10-15% en) during a weight loss intervention lowered plasma triglycerides (TG) by 45% in male subjects (P<.05). However, only those subjects from the EGG group presented higher concentrations of these two carotenoids in plasma, which were correlated with the higher concentra

Acute Ingestion of Long-Chain (n-3) Polyunsaturated Fatty Acids Decreases Fibrinolysis in Men with Metabolic Syndrome. Montegaard C, Tulk HM, Lauritzen L, Tholstrup T, Robinson LE. J Nutr. 2009 Nov 4. [Epub ahead of print] PMID: 19889809 doi:10.3945/jn.109.111427 Individuals with metabolic syndrome (MetS) often have elevated plasma plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (t-PA), contributing to an increased risk of cardiovascular disease. PAI-1 and t-PA may be affected by chronic (n-3) long-chain PUFA [(n-3)LCPUFA] supplementation; however, the acute impact of fat ingestion on these risk factors has not been established. Our objective was to investigate the acute effect of (n-3)LCPUFA on plasma PAI-1, t-PA, and platelet aggregation. We conducted a randomized crossover study in which men (n = 8, ≥45 y) with MetS consumed water or a high-saturated fat beverage (1 g fat/kg body weight) with either a high or low content of (n-3)LCPUFA. Blood samples were collected over 8 h to measure triacylglycerol (TAG), PAI-1, t-PA, and platelet aggregation. Both fat loads resulted in a significant increase in whole blood TAG concentration, plasma PAI-1 and t-PA concentrations, and PAI-1 activity, as well as a significant decrease in t-PA activity during the postprandial period. Interestingly, PAI-1 concentration and activity increased more following the high (n-3)LCPUFA compared with the low (n-3)LCPUFA beverage (P < 0.05). Furthermore, the high (n-3)LCPUFA beverage resulted in a lower t-PA activity (P < 0.05), whereas the effects of the 2 fat loads on the plasma t-PA concentration and platelet aggregation did not differ. Overall, acute intake of a high (n-3)LCPUFA beverage shifted the balance between plasma PAI-1 and t-PA, which might indicate a lower capacity for fibrinolysis

Plasma 25-hydroxyvitamin d is associated with markers of the insulin resistant phenotype in nondiabetic adults. Liu E, Meigs JB, Pittas AG, McKeown NM, Economos CD, Booth SL, Jacques PF. J Nutr. 2009 Feb;139(2):329-34. Epub 2008 Dec 23. PMID: 19106328 doi:10.3945/jn.108.093831 After adjusting for age and sex, plasma 25(OH)D was positively associated with ISI(0,120), plasma adiponectin, and HDL cholesterol and inversely associated with plasma triacylglycerol, but these associations were no longer significant after further adjustment for BMI, waist circumference, and current smoking status. 25(OH)D and 2-h post-OGTT glucose were not associated. Among adults without diabetes, vitamin D status was inversely associated with surrogate fasting measures of insulin resistance. These results suggest that vitamin D status may be an important determinant for type 2 diabetes mellitus.

Vitamin D receptor (VDR) gene polymorphisms and haplotypes, interactions with plasma 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, and prostate cancer risk. Mikhak B, Hunter DJ, Spiegelman D, Platz EA, Hollis BW, Giovannucci E. Prostate. 2007 Jun 15;67(9):911-23. PMID: 17440943 DOI: 10.1002/pros.20570 RESULTS No association was found between these SNPs or their associated haplotypes and all PC subtypes except that haplotype 2 (A-f-b) with Cdx2 A, Fok1 f, and Bsm1 b alleles and haplotype 3 (A-F-B) with Cdx2 A, Fok1 F and Bsm1 B alleles compared to the most common haplotype (A-F-b), were associated with reduced risk of aggressive PC (high stage or Gleason sum 7; P = 0.02), both with two alleles suspected of being low risk. Carriers of the variant Cdx2 A allele who were deficient in plasma 25-hydroxyvitamin D (15 ng/ml) compared to non-carriers with normal 25-hydroxyvitamin D, had a lower risk of total and poorly differentiated PCs (Gleason sum 7) (P for interaction = 0.02 and 0.04, respectively). Plasma 1,25-dihydroxyvitamin D deficiency (26 pg/ml) was associated with a threefold risk of poorly differentiated PC (P for interaction = 0.01) when comparing carriers of the Cdx2 A allele to non-carriers with normal 1,25-dihydroxyvitamin D. CONCLUSION In this population of men, none of the VDR polymorphisms studied was associated with susceptibility to PC. Carriers of the variant Cdx2 A allele with low plasma 25-hydroxyvitamin D may experience a reduction in risk of total and poorly differentiated prostate cancers compared to non-carriers with adequate 25-hydroxyvitamin D.

Plasma 25-hydroxyvitamin D levels and risk of incident hypertension among young women. Forman JP, Curhan GC, Taylor EN. Hypertension. 2008 Nov;52(5):828-32. Epub 2008 Oct 6. PMID: 18838623 doi: 10.1161/HYPERTENSIONAHA.108.117630 Women in the lowest compared with highest quartile of plasma 25(OH)D had an adjusted odds ratio for incident hypertension of 1.66 (95% CI: 1.11 to 2.48; P for trend=0.01). Compared with women with sufficient levels, those with vitamin D deficiency (<30 ng/mL; 65.7% of the study population) had a multivariable odds ratio of 1.47 (95% CI: 1.10 to 1.97). Plasma 25(OH)D levels are inversely and independently associated with the risk of developing hypertension.

Relationships between 25-Hydroxyvitamin D Levels and Plasma Glucose and Lipid Levels in Pediatric Outpatients. Johnson MD, Nader NS, Weaver AL, Singh R, Kumar S. J Pediatr. 2009 Nov 17. [Epub ahead of print] PMID: 19926097 Conclusions Low 25(OH) D levels in children and adolescents are associated with higher plasma glucose and lower HDL concentrations.

Plasma 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D and risk of incident ovarian cancer. Tworoger SS, Lee IM, Buring JE, Rosner B, Hollis BW, Hankinson SE. Cancer Epidemiol Biomarkers Prev. 2007 Apr;16(4):783-8. PMID: 17416771 doi: 10.1158/1055-9965.EPI-06-0981 Overall, our results do not suggest that plasma vitamin D levels are associated with risk of ovarian cancer. However, we observed significant associations in some subgroups, which should be evaluated further in other studies because increasing vitamin D intake is an easy preventive measure to adopt.

Dietary cholesterol from eggs increases plasma HDL cholesterol in overweight men consuming a carbohydrate-restricted diet. Mutungi G, Ratliff J, Puglisi M, Torres-Gonzalez M, Vaishnav U, Leite JO, Quann E, Volek JS, Fernandez ML. J Nutr. 2008 Feb;138(2):272-6. PMID: 18203890 Carbohydrate-restricted diets (CRD) significantly decrease body weight and independently improve plasma triglycerides (TG) and HDL cholesterol (HDL-C) . [..] Eighteen subjects were classified as having the metabolic syndrome (MetS) at the beginning of the study, whereas 3 subjects had that classification at the end. These results suggest that including eggs in a CRD results in increased HDL-C while decreasing the risk factors associated with MetS.

Plasma calcidiol, season, and serum parathyroid hormone concentrations in healthy elderly men and women. Dawson-Hughes B, Harris SS, Dallal GE. Am J Clin Nutr. 1997 Jan;65(1):67-71. PMID: 8988915 Plasma calcidiol and serum PTH concentrations were inversely related, with PTH rising slowly as calcidiol concentrations declined below 110 nmol/L (95 CI: 60, 168 nmol/L). More than 90% of the men and women had calcidiol concentrations below this value in the wintertime. The high prevalence of lower wintertime calcidiol values may increase risk of bone loss in elderly men and women.

Fernandez ML, West KL. Mechanisms by which dietary fatty acids modulate plasma lipids. J Nutr. 2005 Sep;135(9):2075-8. Review. PMID: 16140878 [PubMed - indexed for MEDLINE]

Ordovas JM. The quest for cardiovascular health in the genomic era: nutrigenetics and plasma lipoproteins. Proc Nutr Soc. 2004 Feb;63(1):145-52. Review. PMID: 15070444 [PubMed - indexed for MEDLINE]

Blood pressure and atherogenic lipoprotein profiles of fish-diet and vegetarian villagers in Tanzania: the Lugalawa study. Pauletto P, Puato M, Caroli MG, Casiglia E, Munhambo AE, Cazzolato G, Bittolo Bon G, Angeli MT, Galli C, Pessina AC. Lancet. 1996 Sep 21;348(9030):784-8. PMID: 8813985 Interpretation In these villagers, consumption of freshwater fish (300-600 g daily) was associated with raised plasma concentrations of n-3 polyunsaturated fatty acids, lower blood pressure, and lower plasma lipid concentrations. In conclusion, our findings confirm that the favourable risk factor profile originally described for Eskimos living on a diet rich in n-3 polyunsaturated fatty acids is real, and not overestimated.

Spiller GA, Jenkins DJ, Cragen LN, Gates JE, Bosello O, Berra K, Rudd C, Stevenson M, Superko R.Effect of a diet high in monounsaturated fat from almonds on plasma cholesterol and lipoproteins.J Am Coll Nutr. 1992 Apr;11(2):126-30.PMID: 1315812 [Pub

Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans. Stanhope KL, Schwarz JM, Keim NL, Griffen SC, Bremer AA, Graham JL, Hatcher B, Cox CL, Dyachenko A, Zhang W, McGahan JP, Seibert A, Krauss RM, Chiu S, Schaefer EJ, Ai M, Otokozawa S, Nakajima K, Nakano T, Beysen C, Hellerstein MK, Berglund L, Havel PJ. J Clin Invest. 2009 May;119(5):1322-34. Epub 2009 Apr 20. PMID: 19381015 doi: 10.1172/JCI37385. Studies in animals have documented that, compared with glucose, dietary fructose induces dyslipidemia and insulin resistance. To assess the relative effects of these dietary sugars during sustained consumption in humans, overweight and obese subjects consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 weeks. Although both groups exhibited similar weight gain during the intervention, visceral adipose volume was significantly increased only in subjects consuming fructose. Fasting plasma triglyceride concentrations increased by approximately 10% during 10 weeks of glucose consumption but not after fructose consumption. In contrast, hepatic de novo lipogenesis (DNL) and the 23-hour postprandial triglyceride AUC were increased specifically during fructose consumption. Similarly, markers of altered lipid metabolism and lipoprotein remodeling, including fasting apoB, LDL, small dense LDL, oxidized LDL, and postprandial concentrations of remnant-like particle-triglyceride and -cholesterol significantly increased during fructose but not glucose consumption. In addition, fasting plasma glucose and insulin levels increased and insulin sensitivity decreased in subjects consuming fructose but not in those consuming glucose. These data suggest that dietary fructose specifically increases DNL, promotes dyslipidemia, decreases insulin sensitivity, and increases visceral adiposity in overweight/obese adults.

"MedWire News: Zinc supplements could increase the risk for coronary heart disease (CHD) in healthy people by decreasing high-density lipoprotein (HDL) cholesterol levels, researchers claim. Initial findings from a meta-analysis in 14,238 participants from 20 trials suggested no impact of zinc supplements on plasma lipoprotein levels. But a secondary analysis in healthy individuals showed that zinc was associated with a significant decrease in plasma HDL concentrations. Furthermore, zinc was linked with a significant decrease in HDL cholesterol levels among participants with Type 2 diabetes or those undergoing hemodialysis. The researchers suggest the result in patients with diabetes may relate to the action of zinc in determining insulin levels. The meta-analysis included 33 interventions investigating the impact of zinc on lipid levels. The mean dose of elemental zinc used was 58 mg per day, which the researchers note is beyond the recommended upper level of intake of 40 mg."

The effect of select nutrients on serum high-density lipoprotein cholesterol and apolipoprotein A-I levels. Mooradian AD, Haas MJ, Wong NC. Endocr Rev. 2006 Feb;27(1):2-16. Epub 2005 Oct 21. Review. PMID: 16243964 One of the factors contributing to the increased risk of developing premature atherosclerosis is low plasma concentrations of high-density lipoprotein (HDL) cholesterol (HDLc). Multiple potential mechanisms account for the cardioprotective effects of HDL and its main protein apolipoprotein A-I (apo A-I). The low plasma concentrations of HDL could be the result of increased fractional clearance and reduced expression of apo A-I. To this end, nutrients play an important role in modulating the fractional clearance rate, as well as the rate of apo A-I gene expression. Because medical nutrition therapy constitutes the cornerstone of management of dyslipidemias, it is essential to understand the mechanisms underlying the changes in HDL level in response to alterations in dietary intake. In this review, we will discuss the effect of select nutrients on serum HDLc and apo A-I levels. Specifically, we will review the literature on the effect of carbohydrates, fatty acids, and ketones, as well as some of the nutrient-related metabolites, such as glucosamine and the prostanoids, on apo A-I gene expression. Because there are multiple mechanisms involved in the regulation of serum HDLc levels, changes in gene transcription do not necessarily correlate with clinical observations on serum levels of HDLc.

"I discussed in my last post how Dr Vieth has a model of tissue 1,25(OH)2D synthesis and degradation in which the level of active substance is pretty well independent of blood vitamin D level, provided the level is either rising or stable. I think it is also worth pointing out that he is talking, hypothetically, about tissue 1,25(OH)2D, not plasma level... As we know, almost nothing is known about tissue 1,25(OH)2D control. By Vieth's hypothesis tissue 1,25(OH)2D is OK so long as there is at least SOME vitamin D present in plasma and the level dose not vary too much. Obviously there is a level below which you can have as much of the enzyme for converting vitamin D to the active form as you like, if there is no vitamin D in your blood you can't make any 1,25(OH)2D in your tissues, or in your kidneys for export to your blood to control calcium levels. At the lower extremes we have rickets and osteomalacia. These are clear cut, unarguable markers of vitamin D deficiency, in the absence of confounding factors (there are a few)."

"New research study published in a peer-reviewed publication Nutrition indicates that selenium may be linked to higher cholesterol readings in those who supplement. This one may push it over the edge for me on taking selenium supplements . . . Scientists at the University of Warwick Medical School said consuming too much selenium can have adverse effects. While it has strong antioxidant properties, and the above-mentioned perception that it can reduce cancer risks, there is now an apparently legitimate concern that higher quantities of selenium found in some supplements may be a bad thing. The scientists reached this conclusion after examining the relationship between plasma selenium concentrations (levels of selenium in the blood) with blood lipids (fats in the blood). A cross-sectional study of the1042 participants in the 2000-2001 National Diet and Nutrition Survey (United Kingdom) revealed that among those with higher plasma selenium (more than 1.20 µmol/L) there was an increase in the average total cholesterol level of 8 per cent (0.39 mmol/L (i.e. 15.1 mg/dL). Researchers also found a 10 per cent increase in non-HDL cholesterol levels, which is the bad cholesterol most closely linked to heart disease."

Eggs modulate the inflammatory response to carbohydrate restricted diets in overweight men. Ratliff JC, Mutungi G, Puglisi MJ, Volek JS, Fernandez ML. Nutr Metab (Lond). 2008 Feb 20;5:6. PMID: 18289377 Carbohydrate restricted diets (CRD) consistently lower glucose and insulin levels and improve atherogenic dyslipidemia [decreasing triglycerides and increasing HDL cholesterol (HDL-C)]. We have previously shown that male subjects following a CRD experienced significant increases in HDL-C only if they were consuming a higher intake of cholesterol provided by eggs compared to those individuals who were taking lower concentrations of dietary cholesterol. Here, as a follow up of our previous study, we examined the effects of eggs (a source of both dietary cholesterol and lutein) on adiponectin, a marker of insulin sensitivity, and on inflammatory markers in the context of a CRD. Conclusion A CRD with daily intake of eggs decreased plasma CRP and increased plasma adiponectin compared to a CRD without eggs. These findings indicate that eggs make a significant contribution to the anti-inflammatory effects of CRD, possibly due to the presence of cholesterol, which increases HDL-C and to the antioxidant lutein which modulates certain inflammatory responses.

A nested case control study of plasma 25-hydroxyvitamin D concentrations and risk of colorectal cancer. Wu K, Feskanich D, Fuchs CS, Willett WC, Hollis BW, Giovannucci EL. J Natl Cancer Inst. 2007 Jul 18;99(14):1120-9. Epub 2007 Jul 10. PMID: 17623801