World Dairy Diary

Without lowfat and fat free milk and milk products in the diet, it’s hard to meet nutrient needs, and available research suggests people with lactose intolerance can tolerate at least 12 grams of lactose (the amount in about one cup of milk) with no or minor symptoms. Plus, gradually re-introducing dairy into the diet can help manage symptoms and help those diagnosed benefit from dairy’s unique nutrient package, including calcium, vitamin D, protein, potassium and other nutrients that are critical for bone health and beyond.

Experts also suggest drinking lowfat or fat free milk (regular or flavored) with meals or a snack instead of an empty stomach, trying small, frequent portions or buying lactose-free or lactose-reduced milk – which contain all the same nutrients as regular milk. Yogurt and hard cheeses (the panel suggests cheddar, provolone and mozzarella) may also be more easily digested.
Conducted by the National Institutes of Health since 1977, the Consensus Development Program is an unbiased, independent, evidence-based assessment of complex medical issues. The purpose is to evaluate the available scientific evidence on a medical topic and develop a statement that will advance the understanding of the issue and help guide the advice given by health professionals and directed to the public.

Lactose intolerance is a topic that is frequently misunderstood, according to Dr. Robert P. Heaney, a prominent researcher at Creighton University who presented findings to the panel on the health outcomes of dairy exclusion diets.

The goal of this project was to provide dairy producers information that was not previously available about the potential value of their market cows and bulls. It also underscores that existing industry recommendations to cull animals in a timely manner are one of the best measures to maintain their value and enhance their carcass quality.

While this study does support the concept that premiums exist in the marketplace for market cows of higher quality, an individual operation’s economic analysis should also be a part of the decision-making process.

The primary obstacle to educating dairy producers about Beef Quality Assurance principles has stemmed from the limited income generated from market dairy cows, and an apparent lack of perceived ability to add value. Ultimately, this research will help to meet consumer demand for high-value beef by improving the quality, consistency and safety of beef products from dairy cows.

“There are premiums to be had for producers who sell high-quality market cows. When every dollar counts, it’s important for producers to remember that six percent of total beef production is attributable to market dairy cows,” says Kevin Good, Senior Market Analyst, CattleFax. “Paying attention to quality issues improves salvage value by making animals more desirable for buyers.”

The success of the milk drinkers meant they went on to inhabit most of Europe and explains why everyone who lives on the Continent is tolerant to the milk sugar lactose – unlike 65 per cent of the globe.

It could also be why Europe became the first superpower.

Professor Mark Thomas, an evolutionary geneticist, at University College London, who led the study, said milk was “the world’s first superfood”.

His team used computer models to map the genetic change that enabled early Europeans to evolve their tolerance to lactose after the introduction of cattle farming.

Before this, Stone Age people were “lactose intolerant” – just like many modern humans today, according to the study published in the journal PLoS Computational Biology.

Prof Thomas said: “Conditions were really tough for early settlers. Crops regularly failed and they would have been on the edge of starvation.

“But they had cattle which meant they could produce milk. It would have made some of them sick and given them diarrhoea, and when you are starving this can be fatal. But by building up their tolerance to milk these people were gaining an enormous advantage.

“It was the world’s first superfood and without it the history of northern Europe would have been put back a thousand years.

The dairy is trying out practices and technology that could “help keep small and midrange family dairy farms in business,” Haan said. “It’s not going to happen at 1,000 or 2,000 animal operations.”

In one of the first studies, in 1937-39, the food consumption of children from 1,343 families in England and Scotland were assessed from seven-day household food inventories. The data came from the Carnegie (“Boyd Orr”) survey of diet and health in pre-war Britain.

Now researchers in Bristol and Brisbane, Australia, have carried out a 65-year follow-up study to discover what happened to 4,374 of these children between 1948 and 2005. By 2005, 1,468 (34%) of them had died, including 378 deaths due to coronary heart disease and 121 deaths due to stroke. The researchers looked at two main causes of deaths – stroke and cardiovascular disease.

While warning that other factors may play a part, such as socioeconomic differences, they concluded: “Children whose family diet in the 1930s was high in calcium were at reduced risk of death from stroke.

“Furthermore, childhood diets rich in dairy or calcium were associated with lower all-cause mortality in adulthood.”

Another recent review, in the Journal of the American College of Nutrition, made similar findings. It found that dairy products conferred an “overall survival advantage” against vascular disease, diabetes and cancer.

Judith Bryans, of the Dairy Council, said the findings were clear: people who are well nourished will be healthier.

The review brought together published evidence from 324 studies of milk consumption as predictors of coronary heart disease (CHD), stroke and, diabetes. Data on milk consumption and cancer were based on the recent World Cancer Research Fund report. The outcomes were then compared with current death rates from these diseases.

Professor Givens explained: “While growth and bone health are of great importance to health and function, it is the effects of milk and dairy consumption on chronic disease that are of the greatest relevance to reduced morbidity and survival. Our review made it possible to assess overall whether increased milk consumption provides a survival advantage or not. We believe it does.

“Our findings clearly show that when the numbers of deaths from CHD, stroke and colo-rectal cancer were taken into account, there is strong evidence of an overall reduction in the risk of dying from these chronic diseases due to milk consumption. We certainly found no evidence that drinking milk might increase the risk of developing any condition, with the exception of prostate cancer. Put together, there is convincing overall evidence that milk consumption is associated with an increase in survival in Western communities.”

The reviewers also believe that increased milk consumption is likely to reduce health care costs substantially due to reduced chronic disease and associated morbidity.

In the study, 34 overweight but otherwise healthy men and women participated in two testing sessions – one in which they were served about 20 ounces of fat free milk, and one in which they were served the same amount of a fruit drink (both beverages contributed about 250 calories to the breakfast meal). During the four hours between breakfast and lunch, the men and women gauged their feelings of fullness and were allowed to eat until comfortably full at lunch. The researchers found that the milk-drinking adults reported feeling fuller, more satisfied and therefore ate fewer calories at lunch.

The researchers suspect that milk’s protein content (providing 16% of the daily value per cup), the lactose (the natural sugar in milk) or simply the thickness of the beverage may play a role in the satiety benefits. And, research suggests choosing foods that can help enhance satiety is an important success factor in any weight management plan.

Experts are increasingly focused on small behavior changes that can make a big difference when it comes to maintaining a healthy weight. A calorie decrease as little as 50 calories per day can add up in the long run. Americans may be gaining weight at a rate of up to two pounds per year, likely caused by an average of less than 100 calories per day, according to recent research.

Respondents reported that they paid their workers $506 in average weekly wages, while most also reported providing at least one non‐wage benefit to employees, such as paid vacation, housing, and/or insurance. Those non‐wage benefits brought average dairy workers salaries in 2008 to $31,521, significantly higher than salaries in the landscaping, ranching, and fast food sectors, which employ similar proportions of immigrant workers.

Texas AgriLife Research estimated that if federal labor and immigrant policies were to result in the loss of just half of the 57,000 foreign‐born dairy workers, an additional 66,000 workers would also be lost, due to the closure of some dairy farms, and the resulting multiplier effect of fewer jobs in grain and fertilizer production and sales, veterinary services, milk hauling, and related agricultural service jobs. This would produce an economic loss of $11 billion

“At a time of rising unemployment across America, our elected officials need to understand that the need for rational immigration reform is all the more imperative,” said Jerry Kozak, President and CEO of NMPF. “Congress needs to act quickly to pass legislation such as the AgJobs bill, recently introduced in both the House and Senate. AgJobs is a step towards comprehensive reform of the nation’s immigration laws, which is clearly needed.”

The dairy analysis also indicated that consumers likely would see higher retail dairy product prices, as the loss of farm labor would, in turn, cause farms to reduce or cease their production, reducing the overall U.S. dairy supply. Texas AgriLife Research calculated that a 50% reduction in the dairy immigration workforce would lower milk production by 7.9%, leading to a 30% increase in retail prices.

“Punitive or unworkable labor policies may appear to be intended to help American‐born workers, but what this survey found is that without access to immigrant workers, the economics of the entire dairy industry, as well as many rural communities and other industries, are negatively affected,” said Mike McCloskey, a dairy farmer from Fair Oaks, Indiana, and chair of NMPF’s Immigration Task Force. “You can’t extract immigrant workers out of the equation without creating a negative ripple effect that hurts many other workers as well.”

Weaver said the study, funded by the National Dairy Council, is the first direct comparison of bone properties between calcium from supplements and milk.

“A lot of companies say, ‘If you don’t drink milk, then take our calcium pills or calcium-fortified food,’” Weaver said. “There’s been no study designed properly to compare bone growth from supplements and milk or dairy to see if it has the same effect.”

Data from Purdue’s Camp Calcium, a research effort that studies how calcium and other nutrients affect bone growth, show that between the ages of 9 and 18 people require 1,300 milligrams of calcium a day for optimal bone growth. This is the equivalent of about 4 cups of milk or yogurt or the equivalent from cheese or other sources, Weaver said. After the age of 9, due mostly to peer pressure, the gap between the calcium youths need and actually get widens, she said.

The study involved 300 rats that were divided into two groups. For 10 weeks, the rats were given all the nutrients they require, but one group was given dairy and the other was given calcium carbonate as the source of calcium.

After 10 weeks, the bones of 50 rats from each group were measured for strength, density, length and weight.

“We found those measurements were up to 8 percent higher for those who had milk over calcium carbonate,” Weaver said.

The study also found a strong effect of having dairy as a calcium source followed by periods of inadequate calcium.

Over a second 10-week period, the remaining rats were fed as adults. Half of those were given adequate calcium as carbonate or milk. The other half were switched to half as much calcium as recommended, but were given calcium carbonate.

“This is comparable to humans who, during their early growth, drink a lot of milk to the age of 9 to 11, or maybe even adolescence, but then get only half as much milk calcium as they need after that,” Weaver said. “Some take calcium supplements, but few adults get adequate calcium.”

Weaver said the study showed the rats raised on dairy still had advantages over those who were given calcium carbonate even later when they were given half enough calcium as dairy or calcium carbonate.

“We found it was an advantage having milk or dairy while bones were growing over calcium carbonate, and it protects you later in life,” Weaver said.

She is not sure why dairy is better, but said further study is needed.

“I think this will spark some people to want to figure out what it is about milk that gives it an advantage,” she said.

Hidden in her roughly 22,000 genes are hints of how natural selection sculpted the bovine body and personality over the past 60 million years, and how man greatly enhanced the job over the past 10,000.

As with other species, genes governing the immune system, the metabolism of nutrients and social interaction appear to be where much of the evolutionary action has occurred. The result is an animal that lives peacefully in herds and grows large on low-quality food, thanks to the billions of bacteria it carries around.

Selective breeding has exaggerated and spread some of those traits, producing hyper-passive Holsteins and muscle-bound Belgian Blues, and dozens of humpbacked breeds that combine characteristics of both.

“Are there signatures of the human hand in the cattle genome? The answer is plainly and clearly yes,” said Harris A. Lewin, head of the Institute for Genomic Biology at the University of Illinois at Urbana-Champaign. He is the author of one of three papers on the cow genome appearing today in the journal Science.

Although sheep and goats were domesticated earlier, cattle are the most important herd animals in the world. There are about 800 distinct breeds, and together they contribute to the nutrition or income of about 6.6 billion people.

The cow is the first livestock animal whose genome has been sequenced, part of an effort to read and analyze the DNA of organisms that have scientific, medical or economic importance. In addition to dozens of microbes and several plants, those sequenced so far include the chimpanzee, mouse, rat, dog, chicken, mosquito, fruit fly, opossum and platypus.

Of a cow’s 22,000 genes, versions of at least 14,000 have counterparts in other mammals. Cows appear to have about 1,000 genes that they share with dogs and rodents but that are not found in people.

The most recently evolved genes tend to be clustered in parts of the cow’s 31 chromosomes where stretches of DNA have been duplicated, copied and inserted upside down, or added to by invading viruses. Those events are usually catastrophic and often lead to the fatal breakage of chromosomes. Over evolutionary time, however, a few survive and provide the raw material for new genes — and new functions.

This clear relationship between chromosome instability and gene formation is giving scientists a new view of one way evolutionary change happens at the molecular level.

“Instead of having only a very slow and gradual change by mutation, you have the ability for much larger and dramatic changes because of these rearrangements,” Lewin said.

As a practical matter, having the genome is also going to make cattle breeding faster and cheaper.

Traits carried by bulls are important in determining how much milk a cow produces. Because bulls don’t make milk, however, a bull’s “performance profile” has to be sketched by observing the milk production of his daughters — a process that takes about six years and costs $25,000 to $50,000. Now, male calves can be tested at birth for milk-enhancing traits using gene-chip technology.

“It doesn’t take a rocket scientist to see that makes sense both logistically and financially,” said Curt P. Van Tassell, a geneticist at the U.S. Department of Agriculture’s laboratory in Beltsville, who was one of the leaders of the project.

There are two types of cattle — taurine, which have no humps and predominate in Europe, Africa, the Americas and much of Asia; and indicine, which have humps and are in South Asia and East Africa. Both lineages descended from aurochs, a much larger and more aggressive species.

Indicine breeds have much greater genetic diversity than taurine breeds, evidence that they were developed from a larger number of “founder” animals.

Cows have a large number of genes devoted to big-gun, nonspecific defenses called “innate immunity,” probably reflecting the fact that the animals rely on a huge variety of bacteria and other organisms to digest the roughage they eat.

“They need an immune system that can deal with that large microbial population in close proximity all the time,” said Kim C. Worley, a geneticist at Baylor College of Medicine and one of the leaders of the project.

This new generation vaccine has big benefits beyond eliminating the “Ouch!” factor. Delivering the vaccine to the gut — rather than injecting it into a muscle — harnesses the full power of the body’s primary immune force, which is located in the small intestine.

“This is potentially a great advance in the way we give vaccines to people,” said Mansour Mohamadzadeh, the lead author and an associate professor of medicine in gastroenterology at the Feinberg School.

“You swallow the vaccine, and the bacteria colonize your intestine and start to produce the vaccine in your gut,” Mohamadzadeh said. “Then it’s quickly dispatched throughout your body. If you can activate the immune system in your gut, you get a much more powerful immune response than by injecting it. The pathogenic bacteria will be eliminated faster.”

Most vaccines consist of protein and won’t maintain their effectiveness after being digested by the stomach. However, the lactobacillus protects the vac. The Northwestern study was reported in a recent issue of the Proceedings of the National Academy of Science.

There are other advantages to the new oral vaccine. Probiotics, which are natural immune stimulators, eliminate the need for a chemical in traditional vaccines that inflames the immune system and triggers a local immune response. The chemical, called an adjuant, may cause side effects such as dizziness, arm swelling and vomiting. Probiotic vaccines also are inexpensive to produce.

But because of its huge size — 492,810 people and more than 50,000 cancers — the new study presents powerful evidence favoring the idea that calcium may somehow keep cells from becoming cancerous, said University of North Carolina nutrition expert John Anderson, who wasn’t involved in the study.

The new research involved food questionnaires from participants and a follow-up check of records for cancer cases during the subsequent seven years. This research method is less rigorous than some previous but smaller studies.

National Cancer Institute researcher Yikyung Park, the study’s lead author, called the results strong but said more studies are needed to confirm the findings.

Duke University nutrition researcher Denise Snyder said the results support the idea that food rather than supplements is the best source for nutrients.

Participants were AARP members aged 50 to 71 who began the study in the mid-1990s. A total of 36,965 men and 16,605 women were later diagnosed with cancer. There were more than 10 different kinds of cancer, the most common being prostate, breast, lung and colorectal.

Compared with people who got little calcium, those who consumed the most had the lowest chances of getting colon cancer.

Those in that highest category got on average 1,530 milligrams a day among men and 1,881 milligrams daily among women. The recommended amount for older people is 1,200 milligrams, and getting much more than that didn’t result in any greater protection. Adults can get that amount from four cups of milk or calcium-fortified orange juice.

Men who got the most calcium from food were about 30% less likely to get cancer of the esophagus, about 20% less likely to get head and neck cancer and 16% less likely to get colon cancer, when compared to men who got low amounts of calcium.

Among women, those who got the most food-based calcium were 28% less likely to get colon cancer than low-calcium women.

“Johne’s disease is one of the most important infectious diseases that threatens farmers,” said Yung-Fu Chang, Cornell professor of microbiology and the paper’s principal investigator. “Equally important, though, this organism has been suspected to be one of several possible contributing agents to Crohn’s disease that has similar pathologic lesions in people. The results of our research may offer useful information to those working with Crohn’s disease.”

“But why stop there?” asked researcher Michael Tordoff, a behavioral geneticist at the Monell Chemical Senses Center in Philadelphia. “My group has been investigating what we believe is another taste quality – calcium.”

So assuming the human palate can detect calcium, what does the mineral taste like?

“Calcium tastes calcium-y,” Tordoff said. “There isn’t a better word for it. It is bitter, perhaps even a little sour. But it’s much more because there are actual receptors for calcium, not just bitter or sour compounds.”

One way we might regularly perceive calcium is when it comes to minute levels found in drinking water.

“In tap water, it’s fairly pleasant,” Tordoff said. “But at levels much above that, the taste becomes increasingly bad.”

There may be a strong link between the bitterness of certain vegetables and their calcium level. High-calcium vegetables include collard greens, bok choy, kale and bitter melon. One reason some people might avoid these veggies, Tordoff suggests, is because of their calcium taste.

Ironically, while milk and other dairy products are loaded with calcium, the mineral tends to bind to fats and proteins, which prevents you from tasting it in these foods.

A taste receptor designed specifically for calcium makes sense for our survival, since the mineral is key to cell biology and good bones. Low calcium intakes have been implicated in several chronic diseases in people, including osteoporosis, obesity and hypertension.

“Many animals have a specific calcium appetite, which implies they can detect the mineral and consume sufficient quantities of it to meet their needs,” Tordoff said.

In this study men and women were given a high-calcium diet for seven days, followed by a one-week break, and then a low calcium diet for a further seven days. The fat levels excreted by the participants during both calcium diets were analysed and recorded.

Low-fat dairy foods were the main source of calcium given to the participants, and the researchers found that increasing dairy calcium from 700mg/day to 2300mg/day more than doubled the fat excreted by the participants. They suggested that the calcium may decrease the amount of fat absorbed by the body and this could potentially lead to weight loss.

Another new study, published in Nutrition & Metabolism, found that consuming three portions of dairy a day, as part of a healthy balanced diet may help with weight maintenance.

The subjects were put on a weight-loss diet for the first three months. Those who lost 10kg or 10% of their body weight, were then divided into two groups and followed for a further six months to see if they would maintain their weight. The first group ate three servings of dairy each day, while the second group ate less than one.

At the end of the study, both groups had similar weight and body composition despite a greater calorie intake by the group which had more dairy.

Being able to eat more calories may make it easier for people to stick to a weight-maintenance diet, suggest lead researcher Dr. Michael B. Zemel of the University of Tennessee in Knoxville and his colleagues. Zemel has received grants from the National Dairy Council, and also holds patents on the use of calcium in weight management.

Previous studies have shown that high calcium diets can reduce weight gain and fat accumulation in overfed rats, and may help the animals burn off fat and pounds when their diet is restricted, Zemel and his team note. Some studies in humans have also found that calcium promotes fat loss, possibly by making it harder for the body to hold on to fat cells.

However, no studies in humans have looked at whether calcium and dairy foods help people maintain their weight. To investigate, researchers had 338 obese men and women cut their calorie intake for 3 months.

Study participants who lost at least 10 percent of their weight or 10 kilograms were then randomly assigned to eat less than a single serving of dairy daily or more than three servings a day for the next 6 months.

During the weight maintenance portion of the study, weight and body composition were similar in both groups. However, people in the high-dairy group were eating 9 percent fewer calories than they were at the study’s outset, compared with 22 percent fewer calories for the low-dairy group.

“This suggests that diets with recommended levels of dairy may be higher in energy content (calories) while producing similar effects on body weight and fat as diets low in dairy,” the researchers write.