The team of international researchers followed 4,150 Swedes aged 60 for more than 16 years. They found that those who consumed the most dairy products had a lower risk of cardiovascular disease compared to those who consumed less; the investigation also did not find a link between eating more dairy products and an increased risk of death.
The study did not consider the types of dairy products consumed by the participants. The researchers analyzed the participants’ blood to measure the amount of certain fatty acids associated with dairy products in the blood.
The researchers analyzed the results from Sweden, one of the world’s highest consumers of dairy products, in conjunction with 17 similar studies. The 17 studies involved nearly 43,000 people in several different countries. The results confirmed the Swedish researchers’ findings.
Kathy Trieu, PhD, of the George Institute for Global Health in Australia, lead author of the study paper, said the results of the survey analysis suggest that eating less dairy products may not be the best choice for heart health.
“There is growing evidence that the health effects of dairy products may depend more on their type — for example, cheese, yogurt, milk and butter — than on their fat content. This raises questions about whether avoiding dairy fat altogether is beneficial for cardiovascular health,” she said.
A spokesman for the UK Health Security Agency, which has replaced Public Health England, said the Scientific Advisory Committee on Nutrition (SACN) is considering official guidelines on saturated fats and will “review them in due course. and will publish its report “in due course”.
But they added that “with around 158,000 cardiovascular deaths per year in the UK and saturated fat intake per person still higher than recommended, it remains important to continue to advise and help people to reduce their total saturated fat intake”.
The relationship between dairy products and health
butter
Image credit, GETTY IMAGES
Image annotated with text.
Butter is also a dairy product and is rich in saturated fat.
Many studies have previously shown that dairy products like milk, cheese and yogurt have a neutral, or even positive, effect on reducing the risk of cardiovascular disease, despite being rich in saturated fats. Studies have also found that certain dairy products can also reduce type 2 diabetes and high blood pressure, which are both factors that increase the risk of cardiovascular disease.
Duane Mellor, registered dietitian and head of nutrition and evidence-based medicine at Aston Medical School, said the information we have is that certain dairy products have a protective effect against cardiovascular disease, although we don’t understand the mechanisms and rationale.
For decades, government health policies have recommended that people eat less saturated fat foods. In general, this is based on the fact that saturated fats can increase low-density lipoprotein levels (LDL, also known as bad cholesterol), which can lead to “hardening” of the arteries and increase the risk of heart disease and stroke.
The recommendation does not distinguish between types of saturated fats, in part because most foods, including dairy products, are complex and contain many types of fats.
An emerging theory suggests that the body metabolizes saturated fats known as odd-chain fatty acids differently than others. Small amounts of odd-chain fatty acids can be found in dairy fats, ruminant meats such as cattle, sheep, goats and deer, and in some plants.
It may be that odd-chain fatty acids cannot be used to make low-density cholesterol; or they cannot be recycled; or they are used in different pathways in our bodies,” says Dr. Mellor, “These are just some of the theories that have been explored so far, but more evidence is needed. “
Victoria Taylor, senior nutritionist at the British Heart Foundation, said the link between dairy products and heart and circulatory health is unclear. It may be that the nutrients in dairy products, rather than the specific fatty acids in them, play a key role in protecting the heart.
“Researchers believe that a range of nutrients in milk, including calcium, phosphorus and potassium, may also be involved,” she said, and there is also a suggestion that these nutrients may work together, which is why we see differences across dairy products.
So, do the official health guidelines, which recommend that women and men consume no more than 20/30 grams of saturated fat per day, respectively, need to be changed?
Official dairy intake recommendations
Yogurt
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Yogurt
Susan Jebb, professor of diet and population health at the University of Oxford, says the recommendation for the public to reduce their total saturated fat intake remains the same. Because as a group, we still consume too much saturated fat. Clinical trials have shown that reducing saturated fat reduces bad cholesterol levels, which reduces the risk of cardiovascular disease.
Professor Jebb says she can’t think of any evidence that eating more saturated fat – even dairy products – has health benefits, while reducing saturated fat intake has many benefits – for example, in addition to reducing the risk of cardiovascular disease, eating less meat reduces the risk of colorectal cancer; eating fewer cakes, cookies and pastries also reduces the risk of obesity by lowering sugar and calorie intake.
“That’s probably the biggest diet-related risk factor for heart disease,” Professor Jebb said.
Although cheese contains certain less harmful fatty acids, Professor Jebb said that, as with any healthy dietary structure, the key is moderation, and “in addition to saturated fat, it’s the calorie and salt content of cheese that people need to be aware of.”
Should the public health message be changed?
milk
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Experts say it’s okay to drink a third of a pint of whole milk a day
Dr. Mellor believes it may be time to change the public health message to help reflect the latest research on the heart-protective benefits of eating small amounts of dairy products and to tell the public that they don’t have to shun full-fat dairy altogether.
Cheese and yogurt in dairy products are valuable sources of protein and calcium, he said, and they are “consistently associated” with a reduced risk of cardiovascular disease.
The scientists say the dairy product with the most proven health benefits is hard cheese. It has the property of limiting the amount of fat absorbed by the body, thus reducing the risk of cardiovascular disease. But the evidence for the health protection of butter remains less clear.
Dr. Mellor said, “It’s not that we should eat a lot of full-fat dairy products,” but he believes it’s healthy to consume three small servings of full-fat dairy products per day, such as a thumb-sized piece of cheese, a small bottle of full-fat yogurt and one-third of a pint of whole milk (a pint equals 568 milliliters).
As long as these are included in a diet rich in vegetables and other nutritious foods, Mellor said, there is little problem. The key is to make wise choices when consuming saturated fat foods; the biggest problem is not with full-fat dairy products, but with foods that have little or no nutrition at all.
Dr. Mellor said, “One of the main sources of saturated fat in the British diet is pies (all kinds of sweet and savory pies), pastries, cakes and cookies. These foods contain processed saturated fats. These are something people need to be aware of because they not only contain saturated fat, but also sugar and low-fiber flour.”
Most researchers, including the scientists leading the Swedish study, agree that dairy products are very complex, and whether and how they have a role in protecting the heart is not yet fully understood.
More research is needed to determine the effects of some of the specific fats in dairy products, and/or the various nutrients they contain, on cardiovascular health.