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Vieth R, Fraser D. Vitamin D insufficiency: no recommended dietary allowance exists for this nutrient. CMAJ. 2002 Jun 11;166(12):1541-2. PMID: 12074121 In fact, current recommendations for vitamin D are not designed to ensure anything. They are simply based on the old, default strategy for setting a nutritional guideline, which is to recommend an amount of nutrient similar to what healthy people are eating. This approach underlies the circular logic behind a familiar refrain about nutrition: "If you eat a good diet, you won't need supplements." By this logic, the answer to the question, "How much nutrient do you need?" is, "Whatever healthy people happen to be eating." The essential point, lost in the confusing terminology of modern nutrient recommendations, is that a recommended daily allowance (RDA) does not yet exist for vitamin D. Instead, the recommendations for it are referred to as "adequate intake" (AI).12,13 The AI for young adults (5 µg or 200 IU) was chosen to approximate twice the average vitamin D intake reported by 52 young women in a questionnaire-based study reported from Omaha, Neb., in 1997.13,14 Because the available evidence was acknowledged as weak, the Food and Nutrition Board of the US Institute of Medicine called its recommendation an AI.

Vitamin K content of foods and dietary vitamin K intake in Japanese young women. Kamao M, Suhara Y, Tsugawa N, Uwano M, Yamaguchi N, Uenishi K, Ishida H, Sasaki S, Okano T. J Nutr Sci Vitaminol (Tokyo). 2007 Dec;53(6):464-70. PMID: 18202532 Several reports indicate an important role for vitamin K in bone health as well as blood coagulation. However, the current Adequate Intakes (AI) might not be sufficient for the maintenance of bone health. To obtain a closer estimate of dietary intake of phylloquinone (PK) and menaquinones (MKs), PK, MK-4 and MK-7 contents in food samples (58 food items) were determined by an improved high-performance liquid chromatography method. Next, we assessed dietary vitamin K intake in young women living in eastern Japan using vitamin K contents measured here and the Standard Tables of Food Composition in Japan. PK was widely distributed in green vegetables and algae, and high amounts were found in spinach and broccoli (raw, 498 and 307 microg/100 g wet weight, respectively). Although MK-4 was widely distributed in animal products, overall MK-4 content was lower than PK. MK-7 was observed characteristically in fermented soybean products such as natto (939 microg/100 g). The mean total vitamin K intake of all subjects (using data from this study and Japanese food composition tables) was about 230 microg/d and 94% of participants met the AI of vitamin K for women aged 18-29 y in Japan, 60 microg/d. The contributions of PK, MK-4 and MK-7 to total vitamin K intake were 67.7, 7.3 and 24.9%, respectively. PK from vegetables and algae and MK-7 from pulses (including fermented soybean foods) were the major contributors to the total vitamin K intake of young women living in eastern Japan

Fish consumption shifts lipoprotein subfractions to a less atherogenic pattern in humans. Li Z, Lamon-Fava S, Otvos J, Lichtenstein AH, Velez-Carrasco W, McNamara JR, Ordovas JM, Schaefer EJ. J Nutr. 2004 Jul;134(7):1724-8. PMID: 15226460 The effect of fish consumption on plasma lipoprotein subfraction concentrations was studied in 22 men and women (age > 40 y). Subjects were provided an average American diet (AAD, 35% of energy as fat, 14% as saturated fat, and 35 mg cholesterol/MJ) for 6 wk before being assigned to a National Cholesterol Education Program (NCEP) Step 2 high-fish diet (n = 11, 26% of energy as fat, 4.5% as saturated fat, and 15 mg cholesterol/MJ) or a NCEP Step 2 low-fish diet (n = 11, 26% of energy as fat, 4.0% as saturated fat, and 11 mg cholesterol/MJ) for 24 wk. All food and drink were provided to study participants. Consumption of the high-fish NCEP Step 2 diet was associated with a significant reduction in medium and small VLDL, compared with the AAD diet, whereas the low-fish diet did not affect VLDL subfractions. Both diets significantly reduced LDL cholesterol concentrations, without modifying LDL subfractions. Both diets also lowered HDL cholesterol concentrations. However, the high-fish diet significantly lowered only the HDL fraction containing both apolipoprotein (apo) AI and AII (LpAI:AII) and did not change HDL subfractions assessed by NMR, whereas the low-fish diet significantly lowered the HDL fraction containing only apo AI (LpAI) and the large NMR HDL fractions, resulting in a significant reduction in HDL particle size. Neither diet affected VLDL and LDL particle size. Our data indicate that within the context of a diet restricted in fat and cholesterol, a higher fish content favorably affects VLDL and HDL subspecies

Association between plasma 25-hydroxyvitamin D and breast cancer risk. Crew KD, Gammon MD, Steck SE, Hershman DL, Cremers S, Dworakowski E, Shane E, Terry MB, Desai M, Teitelbaum SL, Neugut AI, Santella RM. Cancer Prev Res (Phila Pa). 2009 Jun;2(6):598-604. Epub 2009 May 26. PMID: 19470790 In summary, these results add to a growing body of evidence that adequate vitamin D stores may prevent breast cancer development. Whereas circulating 25-OHD levels of >32 ng/mL are associated with normal bone mineral metabolism, our data suggest that the optimal level for breast cancer prevention is ≥40 ng/mL. Well-designed clinical trials are urgently needed to determine whether vitamin D supplementation is effective for breast cancer chemoprevention.

Cross-sectional association between fish consumption and albuminuria: the European Prospective Investigation of Cancer-Norfolk Study. Lee CT, Adler AI, Forouhi NG, Luben R, Welch A, Khaw KT, Bingham S, Wareham NJ. Am J Kidney Dis. 2008 Nov;52(5):876-86. Epub 2008 Jun 4. PMID: 18534731 doi:10.1053/j.ajkd.2008.02.307 CONCLUSIONS: Greater fish intake was associated with a lower risk of macroalbuminuria in a self-defined diabetic population. These findings merit confirmation in prospective studies and intervention trials and suggest that fish intake may be beneficial for albuminuria in people with diabetes.

Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU) per day on biochemical responses and the wellbeing of patients. Vieth R, Kimball S, Hu A, Walfish PG. Nutr J. 2004 Jul 19;3:8. PMID: 15260882 doi:10.1186/1475-2891-3-8 CONCLUSION: The highest AI for vitamin D brought summertime 25(OH)D to >40 nmol/L, lowered PTH, and its use was associated with improved wellbeing. The 100 mcg/day dose produced greater responses. Since it was ethically necessary to provide a meaningful dose of vitamin D to these insufficient patients, we cannot rule out a placebo wellbeing response, particularly for those on the lower dose. This work confirms the safety and efficacy of both 15 and 100 mcg/day vitamin D3 in patients who needed additional vitamin D.

Vitamin D status in apparently healthy adults in Kashmir Valley of Indian subcontinent. Zargar AH, Ahmad S, Masoodi SR, Wani AI, Bashir MI, Laway BA, Shah ZA. Postgrad Med J. 2007 Nov;83(985):713-6. PMID: 17989271 doi:10.1136/pgmj.2007.059113 Conclusions: In spite of abundant sunlight, healthy individuals in Kashmir valley are vitamin D deficient, particularly women. Serum 25 (OH) D concentrations are significantly related to sun exposure

Pharmacokinetic and safety profile of trans-resveratrol in a rising multiple-dose study in healthy volunteers.\nAlmeida L, Vaz-da-Silva M, Falcão A, Soares E, Costa R, Loureiro AI, Fernandes-Lopes C, Rocha JF, Nunes T, Wright L, Soares-da-Silva P.\nMol Nutr Food Res. 2009 Feb 4. [Epub ahead of print]\nPMID: 19194969

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.

Dietary Reference Intakes for Vitamin D (1997). National Academy of Sciences. Institute of Medicine. Food and Nutrition Board.

Towards an adequate intake of vitamin D. An advisory report of the Health Council of the Netherlands R M Weggemans, G Schaafsma and D Kromhout Eur J Clin Nutr advance online publication, July 22, 2009; doi:10.1038/ejcn.2009.67

Defining Adequate Vitamin D Intake : Cross-sectional and Intervention Studies Viljakainen, Heli Tuulikki University of Helsinki 2008-05-23 Doctoral dissertation (article-based) Vitamin D is required for normal bone growth and maintenance of the skeleton throughout life. In Finland, like in many other Western countries, the population suffers from inadequate or deficient vitamin D status, especially during winter, which is thought to increase the risk of osteoporosis. New strategies to prevent osteoporosis are actively being sought. The main objective of this thesis was to determine whether vitamin D is feasible in the primary prevention of osteoporosis; does it affect bone mineral accrual during the growth period? A second goal was to ascertain whether seasonal variation in calcitropic hormones affects bone remodelling, and to elucidate the vitamin D intake needed to overcome this variation in different age groups. In summary, vitamin D intake remains inadequate among the target groups of this thesis, as reflected by seasonal variation in calcitropic hormones and bone metabolism. Dietary intake of vitamin D should be increased to achieve at least an adequate vitamin D status (S-25-OHD>50 nmol/l) and possibly an optimal vitamin D status (S-25-OHD>80 nmol/l) throughout the year. This could be accomplished by introducing new vitamin D-fortified foods to the market."