Higher Calcium Intake for at Least a Week or in a Single Meal Increases Fat Utilization, Meta-analysis Concludes

A meta-analysis of eight randomized, controlled trials of calcium's effect on fat oxidation (utilization of fat for energy) found that higher calcium intake (~1,300 milligrams/day vs. ~488 mg/day) over at least seven days significantly increased fat oxidation by 11 percent and contributed to the fat loss benefits of a high-calcium, energy-restricted diet. The authors estimated that an 11 percent increase in fat oxidation would result in the loss of approximately 8 pounds in a year. The effect was the strongest when habitual calcium intake of the participants was low (<700 mg/day). Increasing calcium intake at a single meal also significantly increased fat oxidation, but more studies are needed to confirm these results.

Increasing fat oxidation is one of three major mechanisms that have been proposed to explain how calcium influences body weight. Other studies summarized in previous issues of Dairy Research iNSIGHTS have examined the role of calcium and dairy foods in helping to maintain a healthy weight:

• Observational Data Support the Role of Dairy Consumption in Weight Maintenance Read More
• Increasing Calcium and Dairy Food Intake May Be Part of the Obesity Solution
  Read More

Gonzalez JT, Rumbold PL, Stevenson EJ. Effect of calcium intake on fat oxidation in adults: a meta-analysis of randomized, controlled trials. Obes Rev. [Epub ahead of print]. 2012 June 19.
Abstract

Dietary Patterns That Incorporate Higher Intakes of Dairy Foods May Reduce the Risk of Diabetes in Men

The worldwide prevalence of diabetes is increasing and is projected to rise from 6.4 percent in 2010 to 7.7 percent by 2030 — a majority being type 2 diabetes. A large, five-year prospective study in Australia found that men 25 years old and older who consumed the most dairy foods, compared with the least, had nearly a 50 percent reduced risk of diabetes independent of other risk factors. The researchers primarily attributed the benefit to cheese and low-fat milk intake. Dairy intake also was associated with a nonsignificant trend toward a reduced risk of diabetes among women.

Dairy foods may help reduce diabetes risk through their impact on diabetes risk factors, such as body weight, blood pressure and insulin resistance — though further research is needed to fully understand the potential mechanisms involved. According to the 2010 Dietary Guidelines for Americans, moderate evidence indicates that consumption of milk and milk products is associated with a reduced risk of type 2 diabetes in adults.

Read more about the current research on dairy and diabetes in this concise report.

Grantham NM, Magliano DJ, Hodge A, Jowett J, Meikle P, Shaw JE. The association between dairy food intake and the incidence of diabetes in Australia: the Australian Diabetes Obesity and Lifestyle Study (AusDiab). Public Health Nutr. [Epub ahead of print]. 2012 June 7:1-7.
Abstract

Higher Vitamin D Intake Is Related to Lower 20-Year Incidence of Metabolic Syndrome

Metabolic syndrome, a clustering of cardiovascular risk factors in one individual, can precede cardiovascular events, such as heart attack and stroke. A large, 20-year prospective study in both black and white young adults (18 to 30 years), from the Coronary Artery Risk Development in Young Adults study, found that a higher versus lower vitamin D intake from food and supplements was associated with a 23 percent lower risk of developing metabolic syndrome as the participants reached middle age. This relationship remained statistically significant even after adjusting for the effect of demographics, lifestyle factors and calcium intake. A higher vitamin D intake from food and supplements also was associated with a significantly lower 20-year prevalence of some components of metabolic syndrome, including abdominal obesity, high blood glucose and low HDL-cholesterol.

Milk was the main dietary source of both calcium and vitamin D in this population. This research contributes to the body of literature demonstrating that vitamin D intake may help reduce the risk of chronic disease. The authors say their research "supports the recommendations of the Dietary Reference Intakes and 2010 Dietary Guidelines for Americans to consume vitamin D-fortified milk products, certain types of fish, egg yolks and other foods that are fortified with vitamin D."

Fung GJ, Steffen LM, Zhou X, et al. Vitamin D intake is inversely related to risk of developing metabolic syndrome in African American and white men and women over 20 y: the Coronary Artery Risk Development in Young Adults study. Am J Clin Nutr. [Epub ahead of print]. 2012 May 30.
Abstract

Choosing Milk Over Sugar-sweetened Beverages or Fruit Juice May Significantly Reduce the Risk of Type 2 Diabetes in Women

A prospective study of more than 82,000 women (26 to 45 years) enrolled in the Nurses' Health Study II examined whether the replacement of sugar-sweetened beverages (SSB) and fruit juices with plain water is associated with lower risk of type 2 diabetes. In the process of evaluating different beverages, researchers found that substituting 1 cup of milk (fat-free, low-fat or whole) or coffee for a serving of SSB or fruit juices was associated with a 12 to 17 percent reduction in risk for type 2 diabetes. These risk reductions were greater than when plain water was substituted for SSB or fruit juice (7 and 8 percent, respectively), or when artificially sweetened beverages or tea (5 to 7 percent) were substituted for SSB or fruit juice.

The researchers cited evidence that components in milk such as calcium, magnesium, lactose and dairy protein may have contributed to the additional benefit seen over plain water.

This study is the first to provide evidence that choosing milk over SSBs and fruit juice may help lower the risk of type 2 diabetes. Click here for a report summarizing current research on dairy foods and diabetes.

Pan A, Malik VS, Schulze MB, Manson JE, Willett WC, Hu FB. Plain-water intake and risk of type 2 diabetes in young and middle-aged women. Am J Clin Nutr. 2012;95(6):1454-1460.
Abstract

Whey Protein Consumed at Breakfast and Lunch Does Not Enhance the Effects of Exercise Training on Body Composition or Impact Metabolic Health Outcomes in Middle-aged Overweight Adults

Some research suggests that both exercise and a higher-protein diet may improve body composition and other indices of metabolic health. A 36-week, community-based, randomized, controlled trial in 187 overweight and obese adults (35 to 65 years) examined consuming different amounts of whey protein (0, 20, 40 or 60 grams per day) divided between breakfast and lunch in combination with unsupervised resistance (two days/week) and aerobic training (one day/week).

Researchers found that exercise slightly improved measures of strength, maximal oxygen uptake capacity, lean body mass and fat mass. Whey consumption did not enhance the effects of exercise or have any effects on body composition or any metabolic health outcomes on its own. However, the protein supplement was not consumed immediately after exercise, which previous studies have shown may enhance the effect of whey on muscle protein synthesis. Visit the new microsite on whey protein for further research and information. Neither exercise nor whey had any effects on measures of glucose tolerance, insulin sensitivity or biomarkers of lipid metabolism and inflammation.

Although whey protein supplementation increased total protein intake levels to as high as twice the Recommended Dietary Allowance (RDA), the authors state that participants compensated for the extra calories by decreasing their intake of other foods so that their weight remained stable.

In addition to the timing of whey protein consumption, the authors suggest these unexpected results also may be explained by the fact that the participants were already consuming the RDA for protein at baseline and that fewer than half met the criteria for metabolic syndrome at study onset, making it difficult to detect significant changes.

Additional research is needed to further define the role of dairy protein in metabolic health, with and without exercise.

Weinheimer EM, Conley TB, Kobza VM, et al. Whey protein supplementation does not affect exercise training-induced changes in body composition and indices of metabolic syndrome in middle-aged overweight and obese adults. J Nutr. 2012;142(8):1532-1539.
Abstract

Nutrients Commonly Linked With Lower Risk of Chronic Disease Were Associated With Higher Diet Costs

Nutrients such as vitamins A, C, E, beta carotene, folate, calcium, potassium and fiber have been associated with lower risk of chronic disease. A survey of approximately 1,300 adults in the Seattle area examined how energy-adjusted intakes of key nutrients were related to diet cost (as estimated from food prices at supermarkets in Seattle) and socioeconomic status.

Results showed that:

• Higher intakes of dietary fiber, vitamins A, C, D, E and B12, beta carotene, folate, iron, calcium, potassium and magnesium were associated with higher diet costs.
• In contrast, higher intakes of saturated fats, trans fats and added sugars were associated with lower diet costs.
• Lower-cost, lower-quality diets were more likely to be consumed by those with a lower socioeconomic status.

Calcium and vitamin D — nutrients largely obtained in the diet from milk and milk products — were among the beneficial nutrients that were relatively inexpensive, as were vitamin E, folate and iron. A previous study conducted by one of the same researchers helped identify affordable, nutrient-rich foods. They found that "milk and milk products were by far the lowest-cost source of dietary calcium and were among the lowest-cost sources of riboflavin and vitamin B(12)."

Aggarwal A, Monsivais P, Drewnowski A. Nutrient Intakes Linked to Better Health Outcomes Are Associated With Higher Diet Costs in the US. PLoS ONE. [Epub ahead of print]. 2012 May 25.
Full Article

High-Calcium, Vitamin D-fortified Milk Reduces Markers of Bone Loss and Improves Vitamin D Status in Postmenopausal Chinese Women

The incidence of hip fracture has increased two to threefold in most Asian countries over the last 30 years. A randomized, clinical trial in 63 postmenopausal women living in Beijing, China, found that supplementation with calcium- and vitamin D-fortified milk for 12 weeks, when compared with a placebo, significantly reduced indicators of bone turnover and resorption (breakdown) and improved vitamin D status.

The women in this study were potentially at risk for osteoporosis due to habitually low calcium intakes (<500 milligrams/day) and vitamin D deficiency/insufficiency. The women drank the fortified milk twice a day, which provided a daily total of 900mg calcium, 96mg magnesium, 2.4 mg zinc and 6.4µg (256 I.U.) vitamin D.

Many women over age 50 in the U.S. also have low calcium and vitamin D intakes relative to recommendations — and have low dairy food intakes averaging only 1.25 servings per day — less than half the three servings per day recommended by the 2010 Dietary Guidelines for Americans. Increased intake of milk, with its bone-building nutrients, may help all postmenopausal women reduce their risk of osteoporosis as they age.

Kruger MC, Ha PC, Todd JM, et al. High-calcium, vitamin D fortified milk is effective in improving bone turnover markers and vitamin D status in healthy postmenopausal Chinese women. Eur J Clin Nutr. 2012;66(7);856-861.
Abstract

Dairy Calcium, But Not Calcium Supplements, Is Associated With Lower Risk of Heart Attack

A large, 11-year prospective study in Germany evaluated the associations of dietary calcium intake and calcium supplementation with risk of heart attack, stroke and overall mortality. The study found that a moderately higher intake of dairy calcium (average of 820 milligrams/day), compared with the lowest intake (average of 188 mg/day), was associated with a statistically significant 30 percent lower risk of heart attack. The strongest relationship occurred in women, while in men it was nonsignificant. In contrast, those who used calcium supplements had a statistically significant increased risk of heart attack compared with those who didn’t use any supplements. No overall statistically significant association was found between total, dairy or nondairy calcium intake and stroke risk or cardiovascular mortality.

According to the authors, this is the first observational study to report a possible adverse effect of calcium supplements on risk of heart attack. Several studies have, however, observed an association between higher blood calcium levels and blood vessel calcification — a process that doesn't occur after eating calcium-rich foods. The 2010 Dietary Guidelines for Americans recommends meeting nutrient needs primarily by consuming nutrient-rich foods. Three servings of low-fat or fat-free dairy foods per day is suggested to help meet the calcium needs of individuals age 9 and older.

Li K, Kaaks R, Linseisen J, Rohrmann S. Associations of dietary calcium intake and calcium supplementation with myocardial infarction and stroke risk and overall cardiovascular mortality in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition study (EPIC-Heidelberg). Heart. 2012;98(12):920-925.
Abstract

Meta-Analysis Finds Vitamin D Plus Calcium Supplementation Is Associated With Reduced Risk of Death in the Elderly

During the last decade, there has been increasing recognition of the role of vitamin D in physiological functions beyond bone metabolism. However, evidence that vitamin D influences overall mortality is mixed. A meta-analysis of 24 randomized, controlled trials reporting data on mortality among more than 70,000 elderly adults (62 to 77 years) found that risk of death was significantly reduced if vitamin D was given with calcium, but not when vitamin D was given alone. Mortality was significantly reduced only in participants who consumed 400 I.U. of vitamin D daily (the amount found in four servings of vitamin D-fortified milk) in combination with calcium.

The authors say calcium and vitamin D, when consumed together, may have health effects greater than their individual effects alone. Although the studies included in this analysis used supplemental calcium and vitamin D for their interventions, baseline dietary intakes may have contributed to their beneficial effects. In the U.S., milk is the No. 1 food source of both calcium and vitamin D.

Rejnmark L, Avenell A, Masud T, et al. Vitamin D with Calcium Reduces Mortality: Patient Level Pooled Analysis of 70,528 Patients from Eight Major Vitamin D Trials. J Clin Endocirin Metab. [Epub ahead of print]. 2012 May 17.
Abstract

Adding Salt During the Manufacture of Milk Protein Concentrate Results in Protein Powders That Are Easier to Dissolve

Researchers from the California Dairy Products Technology Center determined that the increase in solubility of milk protein concentrate manufactured with higher sodium content is due to the decrease in bonds between sulfur atoms, reduction in particle size and modification of the hydrophobicity of the powders. These modified milk protein concentrate powders (MPC80) dissolve almost entirely in water if a small quantity of salt is added during the diafiltration part of the manufacturing process. This study provides the dairy industry with the technical insights to expand MPC80 into foods and beverages that require complete solubility of proteins in order to foam, gel or emulsify other ingredients, like oils or flavors.

The researchers created a salt-based MPC80 powder and used fluorescence probes to study the surface of proteins in a dilute water solution. Their study shows that salt makes proteins more water-soluble by changing their structure and behavior. It appears that salt breaks disulfide bonds among individual proteins, which causes proteins to partially unfold and expose their inner fat-soluble (hydrophobic) amino acids to water. Casein micelles were more widely spaced and formed smaller particles. These simple changes in structure result in improved solubility in water for MPC80.

Mao XY, Tong PS, Gualco S, Vink S. Effect of NaCl addition during diafiltration on the solubility, hydrophobicity, and disulfide bonds of 80% milk protein concentrate powder. J Dairy Sci. 2012;95(7):3481-3488.
Abstract

Salt Whey Used to Produce New Process Cheese Product

Researchers at South Dakota State University found an innovative process to recycle salt whey, the byproduct released during cheese pressing, back into cheese products. They modified a formulation for process cheese product by replacing salt with salt whey and by using a young exopolysaccharide (EPS) Cheddar as the base cheese. Frequent cheese consumers could not tell the difference between the process cheese foods in a triangle test.

The other unique ingredient in their research was young, low-sodium Cheddar cheese made with EPS-producing bacteria. EPS consists of long strands of sugar molecules made by bacteria that are the natural thickener found in yogurt and sour cream. In the cheese it formed large pockets, which softened the texture and gave it good melting characteristics. By using a low-sodium, EPS-containing Cheddar as the base, they were able to use up to 13 percent salt whey in their formulation. The new product not only has identical flavor to standard process cheese products, but it actually had a softer texture and better melting properties. This creative use for salt whey is an opportunity for the dairy industry to save on disposal costs, reduce raw ingredients and improve environmental stewardship.

Janevski O, Hassan AN, Metzger L. Application of salt whey in process cheese food made from Cheddar cheese containing exopolysaccharides. J Dairy Sci. 2012;95(7):3609-3616.
Abstract

New Detection Method Could Improve Shelf Life of Pasteurized Milk

Researchers at Cornell University have developed a more rapid and sensitive method to count the number of Paenibacillus spores in milk, which could lead to longer shelf life for fluid milk products. Paenibacillus is a spore-forming bacterium that is able to grow at refrigerated temperatures and may represent more than 95 percent of the bacterial population late in the shelf life of milk. This growth results in off-flavors or curdled pasteurized milk. The current testing procedure takes seven to 10 days and is not specific for Paenibacillus, which limits its ability to forecast shelf life.

The Cornell researchers developed a rapid TaqMan PCR method that traces specific genes back to the offending organism, Paenibacillus species. The new procedure takes three days for low numbers of spores (less than 30/milliliter), with previous research showing that even one spore per milliliter can result in spoiled product at the end of shelf life. The new method also could be used in one day to detect higher numbers of spores when investigating spore sources. Dairy processors can use this quick screening tool to estimate the shelf life of incoming raw milk and perhaps pinpoint the source of contamination.

Ranieri ML, Reid A, Ivy W, et al. Real-Time PCR Detection of Paenibacillus spp. in Raw Milk to Predict Shelf-Life Performance of Pasteurized Fluid Milk Products. App Environ Microbiol. [Epub ahead of print]. 2012 June 8.
Abstract

New Rapid Method to Determine Sodium in Dairy Products Proposed

Italian researchers have developed a new method for determining the amount of sodium in dairy products based on capillary electrophoresis techniques. The most common method of determining sodium cannot differentiate between sodium chloride and potassium chloride nor can it detect nonchloride sodium salts like sodium citrate or sodium lactate. Other procedures like atomic absorption or plasma emission spectroscopy are expensive and slower than the industry needs for v at-to-vat control of sodium. The proposed method should take less than 30 minutes per sample, making it a relatively quick testing procedure that can differentiate between cations.

Capillary electrophoresis uses electric current to move charged particles, such as sodium ions, through an extremely thin tube filled with liquid and then detects the particles as they exit the tube. The rate of movement of the charged particles is dependent on their relative charge and size, which allows the separation and direct detection of sodium, calcium, magnesium and potassium ions, for example. The investigators tested only a limited number of samples, but if the results can be confirmed, then this method would allow greater control of sodium content, less product quality variation and improved consumer satisfaction.

Masotti F, Erba D, De Noni I, Pellegrino L. Rapid determination of sodium in milk and milk products by capillary zone electrophoresis. J Dairy Sci. 2012;95(6):2872-2881.
Abstract

Life Cycle Assessment Studies Provide Standard, But Increased Guidelines Are Warranted

Life cycle assessment (LCA), a method regulated by the International Organization for Standardization (ISO), provides a standard procedure for assessing environmental impacts. This review highlights the need for increased guidelines to better streamline and compare LCA studies of the same product.

Thirteen LCA studies of European milk production were reviewed to identify both the advantages and weaknesses of LCA and to suggest improvements for future studies. Researchers suggested that one strength of the LCA method is that it addresses environmental impacts through the entire life cycle of a product — in this case, milk. However, results are difficult to compare across the 13 milk LCA studies due to differing goals, scope and assumptions. To address this challenge, the authors provided six specific improvements to be addressed.

LCA is the scientific foundation for environmental reporting and product labeling. As consumers and retailers increasingly demand information on the sustainability of products, it is important to develop a uniform methodology for product categories that is in compliance with ISO standards. The Innovation Center for U.S. Dairy^® is currently working with the International Dairy Federation on a common LCA methodology that will support these needs.

Yan M, Humphreys J, Holden N. An evaluation of life cycle assessment of European milk production. J Environ Manage. 2011;92(3):372-379.
Abstract

Dairy Farm Improves Water Quality Through Collaborative Approach With Local Stakeholders

A dairy farm in Vermont employed a five-step collaborative approach to investigate and reduce the level of phosphorus going into the Lake Champlain watershed, thus helping to preserve the health of the ecosystem and the area’s $3.8 billion tourism industry.

Shelburne Farms, a nonprofit environmental education center and working dairy farm, brought together landowners, residents, and researchers to investigate and improve water quality. Lake Champlain receives high levels of phosphorus from the surrounding area. Through their research, Shelburne Farms developed and implemented a storm water treatment system consisting of an inlet pond, rectangular subsurface flow gravel wetlands, vegetated buffer zone surrounding the wetland and an outlet pond. It successfully reduced the amount of phosphorus leaving the farm. However, longer- term evaluations are needed to fully understand the phosphorus reductions and develop ongoing improvement strategies.

The approach was effective in engaging stakeholders, securing funds to implement solutions and providing educational benefits. It serves as a model for adaptive management that meets the needs of multiple stakeholders in a complex agroecosystem.

Kominami H, Lovell ST. An adaptive management approach to improve water quality at a model dairy farm in Vermont, USA. Ecol Eng. 2012;40:131-143.
Abstract

Beverage patterns among Canadian children and relationship to overweight and obesity

Danyliw AD, Vatanparast H, Nikpartow N, Whiting SJ. Appl Physiol Nutr Metab. [Epub ahead of print]. 2012 June 14.
Abstract

An updated systematic review and meta-analysis of the efficacy of vitamin D food fortification

Black LJ, Seamans KM, Cashman KD, Kiely M. J Nutr. 2012;142(6):1102-1108.
Abstract

Relative effectiveness of oral 25-hydroxyvitamin D3 and vitamin D3 in raising wintertime serum 25-hydroxyvitamin D in older adults

Cashman KD, Seamans KM, Lucey AJ, et al. Am J Clin Nutr. 2012;95(6):1350-1356.
Abstract

Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis

Tripkovic L, Lambert H, Hart K, et al. Am J Clin Nutr. 2012;95(6):1357-1364.
Abstract

Vitamin D in food and supplements (Editorial)

Tangpricha V. Am J Clin Nutr. 2012;95(6):1299-1300.
Abstract

Anticarcinogenic effect of probiotic fermented milk and chlorophyllin on aflatoxin-B1-induced liver carcinogenesis in rats

Kumar M, Verma V, Nagpal R, et al. Br J Nutr. 2012;107(7):1006-1016.
Abstract

Oral administration of milk fermented with Lactococcus lactic subsp. cremoris FC protects mice against influenza virus infection

Maruo T, Gotoh Y, Nishimura H, Ohashi S, Toda T, Takahashi K. Lett Appl Microbiol. 2012;55(2):135-40.
Abstract

Effect of dairy protein blends on texture of high protein bars

Imtiaz SR, Kuhn-Sherlock B, Campbell M. J Texture Stud. 2012;43(4):275-286.
Abstract