Nutrition

One-year comparison of a high-monounsaturated fat diet with a high-carbohydrate diet in type 2 diabetes.
Brehm BJ, Lattin BL, Summer SS, Boback JA, Gilchrist GM, Jandacek RJ, D'Alessio DA.
Diabetes Care. 2009 Feb;32(2):215-20. Epub 2008 Oct 28.
PMID: 18957534
doi: 10.2337/dc08-0687

CONCLUSIONS-In individuals with type 2 diabetes, high-MUFA diets are an alternative to conventional lower-fat, high-CHO diets with comparable beneficial effects on body weight, body composition, cardiovascular risk factors, and glycemic control.

July 16, 2008 - Both a low-carbohydrate diet or a Mediterranean-style diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say.

"Several recent one-year dietary studies have led the American Diabetes Association to state in January 2008 that low-carb diets should be considered for a maximum of one year," lead author on the study, Dr Iris Shai (Ben Gurion University of the Negev, Beer-Sheva, Israel), told heartwire . "The current two-year study suggests that one low-fat diet doesn't fit all, meaning that the old paradigm should be reconsidered."

Shai and colleagues publish the results of the Dietary Intervention Randomized Controlled Trial (DIRECT) in the July 17, 2008 issue of the New England Journal of Medicine

July 16, 2008 | Shelley Wood
Beer-Sheva, Israel - Both a low-carbohydrate diet or a Mediterranean-style diet may be "effective alternatives" to a low-fat diet, with more favorable effects on lipids and/or glycemic control, new research suggests [1]. The two-year study, which managed to keep almost 85% of the 322 study participants on one of the three diets for the entire period, offers the hope that weight-loss diets can be tailored to personal preferences, without sacrificing efficacy, researchers say.

"Several recent one-year dietary studies have led the American Diabetes Association to state in January 2008 that low-carb diets should be considered for a maximum of one year," lead author on the study, Dr Iris Shai (Ben Gurion University of the Negev, Beer-Sheva, Israel), told heartwire. "The current two-year study suggests that one low-fat diet doesn't fit all, meaning that the old paradigm should be reconsidered."

Shai and colleagues publish the results of the Dietary Intervention Randomized Controlled Trial (DIRECT) in the July 17, 2008 issue of the New England Journal of Medicine

The Diet-Heart Hypothesis: Subdividing Lipoproteins
Two posts ago, we made the rounds of the commonly measured blood lipids (total cholesterol, LDL, HDL, triglycerides) and how they associate with cardiac risk. It's important to keep in mind that many things associate with cardiac risk, not just blood lipids. For example, men with low serum vitamin D are at a 2.4-fold greater risk of heart attack than men with higher D levels. That alone is roughly equivalent to the predictive power of the blood lipids you get measured at the doctor's office. Coronary calcium scans (a measure of blood vessel calcification) also associate with cardiac risk better than the most commonly measured blood lipids.

Lipoproteins Can be Subdivided into Several Subcategories

In the continual search for better measures of cardiac risk, researchers in the 1980s decided to break down lipoprotein particles into sub-categories. One of these researchers is Dr. Ronald M. Krauss. Krauss published extensively on the association between lipoprotein size and cardiac risk, eventually concluding (source):

The plasma lipoprotein profile accompanying a preponderance of small, dense LDL particles (specifically LDL-III) is associated with up to a threefold increase in the susceptibility of developing [coronary artery disease]. This has been demonstrated in case-control studies of myocardial infarction and angiographically documented coronary disease.

Krauss found that small, dense LDL (sdLDL) doesn't travel alone: it typically comes along with low HDL and high triglycerides*. He called this combination of factors "lipoprotein pattern B"; its opposite is "lipoprotein pattern A": large, buoyant LDL, high HDL and low triglycerides. Incidentally, low HDL and high triglycerides are hallmarks of the metabolic syndrome, the quintessential modern metabolic disorder.

Krauss and his colleagues went on to hypothesize that sdLDL promotes atherosclerosis because of its ability to penetrate the artery wall more easily

"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."

"Tuesday, July 8, 2008
Wheat is Invading China
Dr. Michael Eades linked to an interesting study yesterday on his Health and Nutrition blog. It's entitled "Vegetable-Rich Food Pattern is Related to Obesity in China."

It's one of these epidemiological studies where they try to divide subjects into different categories of eating patterns and see how health problems associate with each one. They identified four patterns: the 'macho' diet high in meat and alcohol; the 'traditional' diet high in rice and vegetables; the 'sweet tooth' pattern high in cake, dairy and various drinks; and the 'vegetable rich' diet high in wheat, vegetables, fruit and tofu. The only pattern that associated with obesity was the vegetable-rich diet. The 25% of people eating closest to the vegetable-rich pattern were more than twice as likely to be obese as the 25% adhering the least.

The authors of the paper try to blame the increased obesity on a higher intake of vegetable oil from stir-frying the vegetables, but that explanation is juvenile and misleading. A cursory glance at table 3 reveals that the vegetable-eaters weren't eating any more fat than their thinner neighbors. Dr. Eades suggests that their higher carbohydrate intake (+10%) and higher calorie intake (+120 kcal/day) are responsible for the weight gain, but I wasn't satisfied with that explanation so I took a closer look.

"DALLAS, Jan. 8 - The same vitamin D deficiency that can result in weak bones now has been associated with an increased risk of cardiovascular disease, Framingham Heart Study researchers report in Circulation: Journal of the American Heart Association.

"Vitamin D deficiency is associated with increased cardiovascular risk, above and beyond established cardiovascular risk factors," said Thomas J. Wang, M.D., assistant professor of medicine at Harvard Medical School in Boston, Mass. "The higher risk associated with vitamin D deficiency was particularly evident among individuals with high blood pressure."

In a study of 1,739 offspring from Framingham Heart Study participants (average age 59, all Caucasian), researchers found that those with blood levels of vitamin D below15 nanograms per milliliter (ng/mL) had twice the risk of a cardiovascular event such as a heart attack, heart failure or stroke in the next five years compared to those with higher levels of vitamin D."

"* Low levels of vitamin D were associated with increased risk of high blood pressure, high blood sugar and metabolic syndrome in teenagers.
* The highest levels of vitamin D were found in whites, the lowest levels in blacks and intermediate levels in Mexican-Americans.

PALM HARBOR, Fla., March 11, 2009 - Low levels of vitamin D were associated with an increased risk of high blood pressure, high blood sugar and metabolic syndrome in teenagers, researchers reported at the American Heart Association's 49th Annual Conference on Cardiovascular Disease Epidemiology and Prevention."

"A new study suggests many Americans aren't getting anywhere nearly enough of the vitamin, and it may be affecting their heart health.

In the study, researchers looked at tens of thousands of healthy adults 50 and older whose vitamin D levels had been measured during routine checkups. A majority, they found, were deficient in the vitamin. About two-thirds had less vitamin D in their bloodstreams than the authors considered healthy, and many were extremely deficient.

Less than two years later, the researchers found, those who had extremely low levels of the vitamin were almost twice as likely to have died or suffered a stroke than those with adequate amounts. They also had more coronary artery disease and were twice as likely to have developed heart failure.

The findings, which are being presented today at an American Heart Association conference in Orlando, don't prove that lack of vitamin D causes heart disease; they only suggest a link between the two. "

Regression of warfarin-induced medial elastocalcinosis by high intake of vitamin K in rats.
Schurgers LJ, Spronk HM, Soute BA, Schiffers PM, DeMey JG, Vermeer C.
Blood. 2007 Apr 1;109(7):2823-31.
PMID: 17138823
DOI 10.1182/blood-2006-07-035345.

This is the first study in rats demonstrating that AC and the resulting decreased arterial distensibility are reversible by high-VK intake

Serum 25-hydroxyvitamin D3 concentrations and carotid artery intima-media thickness among type 2 diabetic patients.
Targher G, Bertolini L, Padovani R, Zenari L, Scala L, Cigolini M, Arcaro G.
Clin Endocrinol (Oxf). 2006 Nov;65(5):593-7.
PMID: 17054459

CONCLUSIONS: Hypovitaminosis D is highly prevalent in type 2 diabetic adults and is strongly and independently associated with increased carotid IMT. Further investigation into whether vitamin D may play a role in the prevention of atherosclerosis appears to be warranted.

Vitamin D deficiency and risk of cardiovascular disease.
Wang TJ, Pencina MJ, Booth SL, Jacques PF, Ingelsson E, Lanier K, Benjamin EJ, D'Agostino RB, Wolf M, Vasan RS.
Circulation. 2008 Jan 29;117(4):503-11. Epub 2008 Jan 7.
PMID: 18180395
doi: 10.1161/CIRCULATIONAHA.107.706127

Conclusions-Vitamin D deficiency is associated with incident cardiovascular disease. Further clinical and experimental studies may be warranted to determine whether correction of vitamin D deficiency could contribute to the prevention of cardiovascular disease.

"Study Shows Vitamin D Supplements May Be Useful in Preventing Heart Disease

Nov. 16, 2009 (Orlando, Fla.) -- Some men with low levels of vitamin D in their blood are at particularly high risk of developing heart disease and weakened bones that can lead to osteoporosis, researchers report.

In a study of more than 1,000 men, those with low levels of both vitamin D and the sex hormone estrogen were at significantly increased risk of having cardiovascular disease, says study head Erin Michos, MD, a cardiologist at Johns Hopkins.

"They were also at dramatically increased risk of osteopenia," or bone loss that can lead to osteoporosis, she says.

"Our results suggest that vitamin D supplements, which are already prescribed to treat osteoporosis, may also be useful in preventing heart disease," Michos tells WebMD.

Men with low levels of vitamin D and testosterone, on the other hand, were not at heightened risk for heart disease or osteopenia."

"18 645 patients with a total cholesterol of 6·5 mmol/L or greater were recruited from local physicians throughout Japan between 1996 and 1999. Patients were randomly assigned to receive either 1800 mg of EPA daily with statin (EPA group; n=9326) or statin only (controls; n=9319) with a 5-year follow-up. The primary endpoint was any major coronary event, including sudden cardiac death, fatal and non-fatal myocardial infarction, and other non-fatal events including unstable angina pectoris, angioplasty, stenting, or coronary artery bypass grafting. Analysis was by intention-to-treat.
Findings
At mean follow-up of 4·6 years, we detected the primary endpoint in 262 (2·8%) patients in the EPA group and 324 (3·5%) in controls-a 19% relative reduction in major coronary events (p=0·011). Post-treatment LDL cholesterol concentrations decreased 25%, from 4·7 mmol/L in both groups. Serum LDL cholesterol was not a significant factor in a reduction of risk for major coronary events. Unstable angina and non-fatal coronary events were also significantly reduced in the EPA group. Sudden cardiac death and coronary death did not differ between groups. In patients with a history of coronary artery disease who were given EPA treatment, major coronary events were reduced by 19% (secondary prevention subgroup: 158 [8·7%] in the EPA group vs 197 [10·7%] in the control group; p=0·048). In patients with no history of coronary artery disease, EPA treatment reduced major coronary events by 18%, but this finding was not significant (104 [1·4%] in the EPA group vs 127 [1·7%] in the control group; p=0·132)."

"Nov 14, 2005 | Michael O'Riordan.
Dallas, TX - The addition of eicosapentaenoic acid (EPA) to low-dose statin therapy significantly reduced the incidence of major coronary events, largely driven by a reduction in unstable angina, when compared with patients taking statins alone. A subgroup analysis of the study, which involved a large number of primary-prevention patients, revealed that statin-treated secondary-prevention patients gained the most benefit from fish-oil supplementation.

Dr Mitsuhiro Yokoyama
Presenting the results of the Japan EPA Lipid Intervention Study (JELIS) during the late-breaking clinical-trials session at the American Heart Association Scientific Sessions 2005, Dr Mitsuhiro Yokoyama (Kobe University Graduate School of Medicine, Japan) said that the mechanism of benefit with EPA, a seafood-based, long-chain, n-3 polyunsaturated fatty acid, appears to be unrelated to the effects of cholesterol lowering.

Commenting on the results of the study for heartwire, Dr Lawrence Appel (Johns Hopkins University School of Medicine, Baltimore, MD) said the findings are impressive given that the benefit of fish oil was observed on top of a regimen of statin therapy. He added that there are still some unknowns about which patient population would benefit most from fish oil."

The first large-scale, prospective, randomized trial of combined treatment with a statin and an omega-3 fatty acid originally derived from fish, eicosapentaenoic acid (EPA), has shown that the addition of EPA to statin therapy provides additional benefit in preventing major coronary events, apparently through lipid-independent mechanisms.[1] The Japan eicosapentaenoic acid (EPA) Lipid Intervention Study (JELIS) tested the effects of long-term use of EPA 1800 mg/day in addition to a statin in Japanese patients with hypercholesterolemia. The results add support to previous evidence of the beneficial effect of omega-3 fatty acids in patients with known coronary heart disease, and show that that effect can extend the benefit of statins, the JELIS investigators believe

High-dose vitamin D3 supplementation in a cohort of breastfeeding mothers and their infants: a 6-month follow-up pilot study.
Wagner CL, Hulsey TC, Fanning D, Ebeling M, Hollis BW.
Breastfeed Med. 2006 Summer;1(2):59-70.
PMID: 17661565
doi:10.1089/bfm.2006.1.59.

Objective: To examine the effect of high-dose maternal vitamin D3 (vitD) supplementation on the nutritional vitD status of breastfeeding (BF) women and their infants compared with maternal and infant controls receiving 400 and 300 IU vitD/day, respectively.

Design: Fully lactating women (n = 19) were enrolled at 1-month postpartum into a randomized- control pilot trial. Each mother received one of two treatments for a 6-month study period: 0 or 6000 IU vitD3 plus a prenatal vitamin containing 400 IU vitD3. The infants of mothers assigned to the control group received 300 IU vitD3/day; those infants of mothers in the high-dose group received 0 IU (placebo). Maternal serum and milk vitD and 25(OH)D were measured at baseline then monthly; infant serum vitD and 25(OH)D were measured at baseline, and months 4 and 7. Urinary calcium/creatinine ratios were measured monthly in both mothers and infants. Dietary and BF history and outdoor activity questionnaires were completed at each visit. Changes in skin pigmentation were measured by spectrophotometry. Data were analyzed using chi-square, t-test, and analysis of variance (ANOVA) on an intent-to-treat basis.

Conclusion: With limited sun exposure, an intake of 400 IU/day vitamin D3 did not sustain circulating maternal 25(OH)D levels, and thus, supplied only extremely limited amounts of vitamin D to the nursing infant via breast milk. Infant levels achieved exclusively through maternal supplementation were equivalent to levels in infants who received oral vitamin D supplementation. Thus, a maternal intake of 6400 IU/day vitamin D elevated circulating 25(OH)D in both mother and nursing infant.

A phase 2 trial exploring the effects of high-dose (10,000 IU/day) vitamin D(3) in breast cancer patients with bone metastases.
Amir E, Simmons CE, Freedman OC, Dranitsaris G, Cole DE, Vieth R, Ooi WS, Clemons M.
Cancer. 2009 Nov 13. [Epub ahead of print]
PMID: 19918922
DOI: 10.1002/cncr.24749

METHODS:
Patients with bone metastases treated with bisphosphonates were enrolled into this single-arm phase 2 study. Patients received 10,000 IU of vitamin D3 and 1000 mg of calcium supplementation each day for 4 months. The effect of this treatment on palliation, bone resorption markers, calcium metabolism, and toxicity were evaluated at baseline and monthly thereafter.


CONCLUSIONS:
Daily doses of 10,000 IU vitamin D3 for 4 months appear safe in patients without comorbid conditions causing hypersensitivity to vitamin D. Treatment reduced inappropriately elevated parathyroid hormone levels, presumably caused by long-term bisphosphonate use. There did not appear to be a significant palliative benefit nor any significant change in bone resorption. Cancer 2010. © 2009 American Cancer Society.

The polyp prevention trial continued follow-up study: no effect of a low-fat, high-fiber, high-fruit, and -vegetable diet on adenoma recurrence eight years after randomization.
Lanza E, Yu B, Murphy G, Albert PS, Caan B, Marshall JR, Lance P, Paskett ED, Weissfeld J, Slattery M, Burt R, Iber F, Shike M, Kikendall JW, Brewer BK, Schatzkin A; Polyp Prevention Trial Study Group.
Cancer Epidemiol Biomarkers Prev. 2007 Sep;16(9):1745-52.
PubMed PMID: 17855692
doi: 10.1158/1055-9965.EPI-07-0127

his study failed to show any effect of a low-fat, high-fiber, high-fruit and -vegetable eating pattern on adenoma recurrence even with 8 years of follow-up.

Influence of a diet very high in vegetables, fruit, and fiber and low in fat on prognosis following treatment for breast cancer: the Women's Healthy Eating and Living (WHEL) randomized trial.
Pierce JP, Natarajan L, Caan BJ, Parker BA, Greenberg ER, Flatt SW, Rock CL, Kealey S, Al-Delaimy WK, Bardwell WA, Carlson RW, Emond JA, Faerber S, Gold EB, Hajek RA, Hollenbach K, Jones LA, Karanja N, Madlensky L, Marshall J, Newman VA, Ritenbaugh C, Thomson CA, Wasserman L, Stefanick ML.
JAMA. 2007 Jul 18;298(3):289-98.
PMID: 17635889

Conclusion Among survivors of early stage breast cancer, adoption of a diet that was very high in vegetables, fruit, and fiber and low in fat did not reduce additional breast cancer events or mortality during a 7.3-year follow-up period.