Introduction: Nutritional advice is everywhere, but how do you know what to trust? One topic that has been widely discussed is the relationship between diet and cholesterol levels; if you eat more cholesterol then your total cholesterol will be higher, right? In this blog post, we will explore the emerging science behind cholesterol metabolism and what aspects of your diet might not be the primary factor influencing your cholesterol levels.
Understanding Cholesterol: Cholesterol is a fatty substance essential for building cell membranes and producing hormones in the body. Fats and water don’t mix well so cholesterol needs a ship to “piggyback” upon. The ship which transports cholesterol through the bloodstream is protein, hence the true name of cholesterol; lipoproteins.
The Role of Genetics: Genetics play a role in how our bodies metabolize cholesterol. Every individual processes molecules at slightly different rates however this does not account for the nearly 40 million people who have high cholesterol levels. Approximately 1 out of 250 individuals has a genetic condition where they produce a greater than normal level of cholesterol. If 1 out of every 250 people have this genetic predisposition, how do we arrive at the vast number of 40 million?
Where does cholesterol come from? Our body makes the cholesterol that it needs, mainly in the liver. Cholesterol is used by the body to make hormones like testosterone and estrogen, it’s used to make certain vitamins and is a significant part of the cellular structure. A small percentage, 15-20% of the cholesterol we eat gets absorbed; the remaining ~80% stays in the intestine and is eliminated.
Dietary Impacts:
Trans Fats: The consumption of trans fats has a well-established correlation with elevating cholesterol levels. Foods high in these fats are processed foods such as snack cakes, cookies, crackers, and margarine. These trans fats have actually shown to promote cholesterol production. Therefore, focusing on a balanced diet that limits the intake of trans fats remains an important aspect of heart health.
Saturated fats: Up for a great deal of debate is whether or not consuming saturated fats significantly elevates your cholesterol levels. Saturated fats, such as bacon and red meats, contain cholesterol so the idea is that eating these foods will cause your cholesterol to go up as a result. As mentioned above, only 15-20% of the cholesterol we eat gets absorbed so let’s put that into perspective. If we were to eat ground beef, we’d need to eat nearly 14 pounds to achieve the amount of cholesterol your body needs on a daily basis. Furthermore, saturated fats do not cause the body to produce cholesterol at an elevated rate, such as in the case of trans fats.
Carbohydrates: There are many health benefits to consuming certain carbohydrates, such as vitamin C, E, selenium, and fiber. Unfortunately, most refined carbohydrates have been stripped of much of their nutritional content, specifically fiber. Fiber helps to slow down the absorption of sugar which is why fiber is so beneficial. The faster we absorb glucose, the more cholesterol our livers produce. So if we wish to have better control over our cholesterol levels, focusing on our simple carbohydrate intake would serve us far better than focusing on our fat intake.
Lifestyle Factors: Other lifestyle factors, including physical activity, smoking, and stress, can significantly impact cholesterol levels. Regular exercise has been shown to increase HDL cholesterol, the "good" cholesterol that helps remove LDL cholesterol from the bloodstream. Conversely, smoking and chronic stress can contribute to inflammation and negatively affect cholesterol balance.
The Mediterranean Diet Paradigm: The Mediterranean diet, characterized by high consumption of fruits, vegetables, whole grains, and healthy fats like olive oil, has been associated with a lower risk of heart disease. This diet is NOT low in cholesterol, it IS low in refined carbohydrates and HIGH in fiber intake. The emphasis on monounsaturated fats, antioxidants, and fiber in the Mediterranean diet may contribute to its positive impact on heart health.
Conclusion: As we navigate the complex relationship between diet and cholesterol levels, it's essential to recognize that the picture is more nuanced than previously thought. While dietary cholesterol may have a limited impact on blood cholesterol for many individuals, genetics, lifestyle factors, and the types of fats consumed play crucial roles. Before making significant changes to your diet, it's advisable to consult with a healthcare professional who can provide personalized guidance based on your unique health profile. Ultimately, a holistic approach to heart health that considers various factors will contribute to a more accurate understanding of cholesterol management.
Comments