The findings were the same for both whole-fat and low-fat dairy, reported Mahshid Dehghan, PhD, of McMaster University in Hamilton, Ontario, and colleagues in The Lancet. The risk of death due to non-cardiovascular disease is also lower for those who eat full-fat dairy.
To study the impact of dairy on heart health, the researchers examined data from over 136,000 people, aged 35 to 70, in 21 countries.
However, Associate Professor Anna Rangan of Sydney University warned: "The results only suggest the consumption of dairy products should not be discouraged and perhaps even encouraged in low-income and middle-income countries".
Dehghan and her co-authors note that the long-standing recommendation to consume low-fat dairy rests on concern over saturated fat, which has always been vilified for its links to cardiovascular disease.
The authors say that more research into why dairy might be associated with lower levels of cardiovascular diseases is now needed. The researchers are now performing another analysis of the data, one looking at the association between dairy and cardiometabolic risk factors, and they have observed significantly lower blood pressure among those who consumed more dairy, she said.
Dairy consumption was highest in North America and Europe (368g each day or above four servings of total dairy per day) and lowest in south Asia, China, Africa and south east Asia (less than one serving of total dairy per day). A new large study however, has now shown that full-fat dairy and dairy products may be more beneficial for the heart.
When compared with those no consuming milk, the high intake group had lower rates in four categories - total mortality of 3.4 percent vs. 5.6 percent, non-cardiovascular mortality of 2.5 percent vs. 4 percent, cardiovascular mortality of 0.9 percent vs. 1.6 percent, major cardiovascular disease of 3.5 percent vs. 4.9 percent and stroke of 1.2 percent vs. 2.9 percent. This new finding is contrary to conventional dietary guidelines.
The Express suggested the study represented a "moo-turn" and called into question national guidelines which encourage people to opt for low-fat dairy products in order to lower their saturated fat intake.
A serving was determined as being equivalent to a glass of milk, a cup of yoghurt, one 15 gram slice of cheese, or a teaspoon of butter.
"However, as the authors themselves concluded, the results only suggest the 'consumption of dairy products should not be discouraged and perhaps even be encouraged in low-income and middle-income countries'".
Dehghan pointed out that some people avoid dairy because of its saturated-fat content, because fat has more calories and because saturated fat has been linked to higher "bad" LDL cholesterol levels.
Earlier this year the Government's Scientific Advisory Committee on Nutrition (SACN) published a consultation on saturated fat, which is part of a process of regularly assessing available evidence to see if guidelines should change.
But in doing so, they are missing out on other important nutrients that dairy provides, such as amino acids, vitamins and minerals, she added.
There were no noteworthy connections between myocardial infarction and dairy intake (HR 0.89, 95% CI 0.71-1.11; P=0.163). "Therefore, when you're focusing on low-fat dairy, we're scaring people about the harms". "Three servings is moderate consumption, and moderate consumption is beneficial". While multiple weighted food records may be more accurate, they require extensive training, motivation, awareness and literacy which limits the practicality for such a large long-term study. In this study the people with higher intakes were having about two to three portions of dairy a day, which is in line with current advice. "However, ideally our findings require confirmation in randomized trials evaluating the effects of increasing dairy consumption on BP, glucose, and clinical outcomes", Dehghan added.