Which is better for the heart: whole milk or low-fat milk?
Nour Nour Eldin – The glass of milk we drink in the morning may seem like a simple dietary choice, but does opting for whole milk versus low-fat milk make a difference for long-term heart health? A broad Norwegian study suggests the answer may be yes. Researchers found that consumption of whole milk was associated with an increased risk of death, including death from cardiovascular diseases, compared to lower-fat milk. These findings emerge at a time when the impact of dairy products on heart health remains a subject of scientific debate, particularly since these products contain beneficial nutrients such as protein and calcium, but may also be a significant source of saturated fats when consumed in their whole-fat form.
The new study, published in The American Journal of Clinical Nutrition, relied on data from 73,860 Norwegian participants collected across three counties between 1974 and 1988. The Norwegian population is particularly interesting in this context due to its historically high milk consumption. Researchers analyzed the relationship between milk intake and overall mortality, as well as death from cardiovascular diseases, ischemic heart disease, and myocardial infarction. When analyzing milk consumption, they found that individuals who consumed the largest amounts had a 12% higher risk of death from cardiovascular diseases and a 22% higher risk of death from any cause compared to those who consumed smaller amounts.
**Low-fat linked to better outcomes**
When comparing milk types, researchers found that low-fat milk consumption was associated with lower mortality rates compared to whole milk. This included deaths resulting from cardiovascular diseases, ischemic heart disease, and myocardial infarction, as well as all-cause mortality. The researchers concluded that lower-fat milk may be associated with reduced risks compared to whole milk.
The difference between the two types is not trivial in terms of fat content; a liter of semi-skimmed milk contains, on average, about 15 to 18 grams of fat, compared to approximately 35 grams in whole milk. Skimmed milk, meanwhile, contains less than 5 grams of fat per liter.
**Is saturated fat the culprit?**
This is one possible explanation. Whole-fat dairy products provide a larger amount of saturated fatty acids. When these fats replace unsaturated fats in the diet, they can lead to elevated LDL (“bad”) cholesterol, thereby increasing cardiovascular risk. Consequently, when attempting to lower cholesterol, health guidelines recommend limiting excessive intake of saturated fats found in sources such as butter, cheese, and meat, and replacing part of them with unsaturated fats found in olive oil, nuts, certain vegetable oils, and fish.
However, the relationship between dairy products and heart health is more complex than just the amount of saturated fat, as the impact of the product may vary depending on its type, manufacturing method, and nutritional composition.
**Should we immediately replace whole milk?**
For individuals who consume milk regularly, especially those with elevated cholesterol levels or cardiovascular risk factors, choosing low-fat or skimmed milk can be a simple way to reduce saturated fat intake without giving up milk altogether. However, heart health does not depend on a single glass of milk. Cardiovascular risk is influenced by the overall diet, as well as physical activity, smoking, blood pressure, cholesterol, diabetes, weight, and genetic factors. Therefore, the benefit of consuming low-fat milk instead of whole milk will be limited if the rest of the diet remains rich in processed meats, fried foods, sugars, and ultra-processed items.
