Milk forms a part of our daily diet – be it as whole milk or different dairy products such as cheese, cream and yogurts. As with any other naturally available food, milk and its products contain within them fats and cholesterol. Here we shall take a closer look at dairy products and cholesterol.
The level of cholesterol in the blood is reflective of the amount of fat in the circulation, and is directly related to the risk of developing cardiovascular disease. There are 2 main kinds of cholesterol – High Density Lipoprotein (HDL) cholesterol, also called good cholesterol and Low Density Lipoprotein (LDL) cholesterol, also called bad cholesterol. While the former protects the arteries from clogging up with fat deposits, the latter is responsible for cardiovascular disease in the form of heart attacks and strokes. It is important to bear in mind that while high levels of blood cholesterol is associated with higher chance of developing cardiovascular disease, fat consumption is essential to maintain normal organ function, hormone production and cell metabolism.
Milk is commercially available in variety of forms and is not just limited to cow’s milk. People who enjoy dairy products have to keep in mind that they contain a variety of different fats within them. Whole milk cholesterol is the highest amongst the available forms of milk, while skimmed milk cholesterol is the lowest. Furthermore, saturated fats are higher in whole milk products which are a risk factor for developing heart disease and atherosclerosis (thickening and furring up of arteries due to deposition of fat). Skimmed milk cholesterol levels are extremely low as most of the fats are removed during the skimming process. It is believed to be healthier than other forms of dairy, and there also appears to be some evidence that it lowers blood pressure (see later). But the presence of different levels of fat should not put one off from consuming dairy products. They are rich in calcium and vitamin D which are essential to maintain bone health. They are also rich in vitamins and minerals. These are required from normal functioning of muscles and blood vessels.
The presence of cholesterol is not only limited to cow’s milk. There are other forms of milk that are consumed these days that also contain cholesterol and should be kept an eye on when it forms a part of the regular diet. These include –
Goat’s milk cholesterol levels appear to be a bit higher than the cow’s. But whether or not this is exactly true is still unclear. While the overall fat levels are higher in goat’s milk, it may well be that the cholesterol levels are lower.
Coconut milk cholesterol is non-existent but the levels of saturated fats are very high when compared to its animal counterpart. While technically not a ‘milk’, it is commonly used in cooking in Indian and Thai cuisine. Intake should be limited to reduce risk of developing atherosclerosis and cardiovascular disease.
Soy milk cholesterol does not seem to be too much of a concern as studies have been conducted that have in fact assessed the cholesterol lowering properties of soy milk. LDL levels have been shown to be reduced by around 5% after 4 weeks in a study where subjects consumed soy milk 3 times a day. Evidence also suggests that HDL cholesterol levels were raised, thus offering a protective effect to the heart.
There is a plethora of evidence suggesting a detrimental role of cholesterol, particularly LDL cholesterol in the development of cardiovascular disease. By itself, or combined with other risk factors such as smoking and high blood pressure, high cholesterol promotes the development of atherosclerosis, which is a key factor in the development of heart attacks and strokes. This means that people who have high cholesterol have a higher chance of dying from these illnesses than others. Consuming excessive whole cow’s milk, coconut milk and goat’s milk will increase this risk dramatically.
When it comes to keeping cholesterol low, it is a good idea to limit products made of whole milk. Skimmed milk options and low fat dairy choices are easily available these days that are a lot healthier. Cholesterol build up within the arteries occurs at a young age and observing these simple steps can keep blood cholesterol levels at bay. Furthermore, skimmed milk consumption has been demonstrated from studies to lower blood pressure, and this is discussed next.
In the recent years, studies have been conducted looking at the effect of milk on the high blood pressure. In fact, in a study published in Hypertension (an American Heart Association journal), regular consumption of low fat milk was associated with a reduction in the risk of developing high blood pressure. But how is this effect exerted? Cow’s milk contains different types of protein peptides within it. When fermented with different bacteria, it breaks dairy down into these different peptides which are then believed to bind to a certain enzyme called Angiotensin Converting Enzyme that controls blood pressure, thus reducing it. In addition, it is also been shown that these peptides can bind to opioid receptors and exert a morphine like effect which also reduces blood pressure. Other studies have shown that the presence of calcium and vitamin D in the milk can also reduce blood pressure, but other co-existing factors such as absorption of calcium have to be considered when interpreting the results. While these study results do look promising, more research will have to be conducted to ascertain the amount of milk that has to be consumed in order to exert an anti-hypertensive effect.
There is no doubt that there is a direct link between milk consumption and cholesterol levels. However, simple changes can be made that can help keep cholesterol levels low, while maintaining a normal blood pressure.