Providing general advice about diet and health that applies to everybody is a very difficult task. Therefore, public health guidelines generally focus on recommendations that guarantee adequate nutrition, vitamins and minerals. Furthermore, they emphasise balancing calorie intake with physical activity. Dietary guidelines for Americans 2010 recommend eating healthy foods like vegetables, fruits, whole grains, fat-free or low-fat dairy products, seafood, and to consume less sodium, saturated fats, trans fats, added sugars, and refined grains. However, when it comes to the individual, what is best in each case varies greatly. Individual recommendations have to take into account factors such as height, weight, BMI, body stature, waistline and metabolic function. Does he individual suffer from diabetes, high blood pressure, lipid problems, heart disease or obesity? Therefore, my belief is that dietary recommendations have to be tailored to the individual needs.
As a physician, I have a very broad view when it comes to diet and nutrition. I am not a fan of a certain diet. Many people do very well on a balanced diet as suggested by the dietary guidelines. However, I have doubts concerning the overemphasis on low fat, as suggested by the guidelines. “Low fat ” has almost become synonymous with “good health”. I have nothing against low fat diets. However, I doubt that the emphasis on low fat, low saturated fat in particular, is based on good scientific evidence. Furthermore, I believe that the overemphasis on low fat may have stimulated consumers and manufacturers to choose foods that may be potentially harmful and could have contributed to the so-called obesity epidemic and increased incidence of type 2 diabetes.
A low fat diet may be preferable for some individuals while other individuals may do better on a low carbohydrate diet. The fact that I may recommend a Paleo or an Atkins type diet for some people, does not mean that I am against whole corn bread or potatoes. Although I recommend everybody to avoid simple refined sugars and junk food, I think complex carbohydrates, starches and not least fiber should be a part of a healthy diet for most people.
As a cardiologist, I see many patients who are overweight or obese. Many of these individuals suffer from the metabolic syndrome. It is estimated that nearly one of every four American adults suffer from this condition. These individuals have an increased risk of developing type -2 diabetes and heart disease. The metabolic syndrome is commonly associated with increased waist circumference, elevated blood pressure, elevated triglycerides, reduced levels of HDL – cholesterol (the good cholesterol), elevated blood sugar (glucose) and insulin levels. Treating and preventing this condition is of huge importance for the community and a great challenge for health professionals.
For many years, I was hugely sceptical about recommending low carbohydrate, high fat diets (LCHF) to patients with overweight or obesity. Like so many of my colleagues, I was afraid such lifestyle might elevate blood cholesterol and increase the risk of coronary heart disease. However, during the last ten years or so, scientific studies have shown that LCHF diets may indeed be helpful if you suffer from overweight or obesity. They may not only help you lose weight, but they may also improve your general health in many ways. However, it was not until I had read three of my favorite books on the subject, “Good Calories Bad Calories” by Gary Taubes, “Living Low Carb” by Jonny Bowden and “The Art and Science of Low Carbohydrate Living” by Jeff S Volek and Stephen D Phinney that I gained enough courage to give it a try. I started with my self and enjoyed very good results. Since then I have been educating a number of may patients with overweight, obesity or signs of the metabolic syndrome about the possible health benefits of LCHF. I have seen many of them having a great success with this lifestyle. Most have managed to improve their general health and modifiy their cardiovascular risk factors in a positive way. I am absolutely not saying that other methods don´t work, but I can confirm that LCHF very often works in real life if you suffer from overweight or obesity.
There is much evidence suggesting that people with the metabolic syndrome suffer from carbohydrate intolerance, a phenomenon that is associated with high levels of insulin and insulin resistance. This implies that there is an exaggerated glucose and insulin response to a given amount of carbohydrate ingested. Glucose uptake by muscles may be impaired which may help divert ingested carbohydrate to the liver where it is converted to fat. This may lead to elevated triglycerides and other lipid problems.
Let´s say you decide to give it a try. You decide to avoid refined sugars entirely, throwing candy and beverages out of the window. You also cut down on other types of carbohydrates, avoiding potatoes, bread, corn, pasta and rice. Basically, the only carbohydrates you will eat are those found in vegetables and fruit, but you may want to limit them as well. To provide the body with energy, you will increase the consumption of natural healthy fats. You will eat dairy fat, animal fat and plant derived fat. You will avoid low fat dairy products because they are usually rich in artificial sugar. Then slowly, later on, you start selectively adding carbohydrate to your diet, in the amount tolerated so that you will not start to gain weight again.
Just remember, before you do it, consult your doctor and ask for his advice, because there might be individual issues that have to be addressed. Have baseline tests performed, let him or her check your blood pressure, blood sugar and blood lipids (total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides). In three to six months you can check these markers again for comparison. And don´t forget to follow the advice of experts in the field or people who have experience, because there may be some pitfalls. For example, you may have to drink broth regularly because of the sodium loss that commonly accompanies LCHF diets.
What can you expect? How will this lifestyle change affect our health? This is what is likely to happen following carbohydrate restriction. Keep in mind though, that there is individual variation, people do not all respond in exactly the same way.
Ten benefits of a low carbohydrate diet.
1. You will lose weight
Scientific studies and years of experience have shown that weight loss will occur on a LCHF diet. The amount of weight loss may vary between individuals and will also depend on how aggressive you are in getting rid of sugar and carbs.
2. Blood sugar will improve
Studies have shown that low carbohydrate diets reduce levels of fasting glucose and glycohemoglobin. This may be beneficial, in particular if you have diabetes or prediabetes, which is quite common among individuals with the metabolic syndrome.
3. Blood pressure will improve
High blood pressure is one of the strongest known risk factors for stroke and heart disease. Lowering blood pressure is therefore considered a very important step to lower the risk of cardiovascular disease. Studies indicate that LCHF diets lower blood pressure in in individuals with overweight or obesity.
4. Triglycerides will improve
Blood levels of triglycerides have emerged as a very important risk factor for cardiovascular disease. High serum triglyceride level is associated with abnormal lipoprotein metabolism, as well as with other risk factors including obesity, insulin resistance, diabetes mellitus, and lowered levels of HDL- cholesterol. It has been shown in a number of studies that carbohydrate restriction lowers triglyceride levels significantly.
5. HDL – cholesterol will improve.
HDL cholesterol is inversely related to both coronary heart disease and other cardiovascular disease mortality in both man and women. This means that low levels of HDL-cholesterol are associated with risk of heart disease. Carbohydrate restriction has been shown to increase blood levels of HDL-cholesterol.
6. LDL-particle size will improve
LDL-Cholesterol particles exist in different sizes. On one hand we have the large, fluffy, cotton-ball like molecules, and on the other hand the small dense molecules. Many recent studies have looked into the importance of LDL-particle size. Studies show that people whose LDL-C particles are predominantly small and dense, have a threefold greater risk of coronary heart disease. Furthermore, the large and fluffy type of LDL-C may actually be protective. Studies indicate carbohydrate restriction positively affects particle size by reducing the number of very small and small LDL particles.
7. LDL-particle number (LDL-P) will improve
Blood levels of LDL-P are strongly associated with the risk of cardiovascular disease and some studies indicate that LDL-P may be a stronger predictor of risk than the commonly used LDL-cholesterol. LCHF diets appear to significantly reduce LDL-P.
8. Insulin resistance will be reduced
Insulin resistance is common in individuals with the metabolic syndrome and is strongly related abnormal lipid profile. There appears to be an association between insulin resistance and cardiovascular disease. Studies indicate that carbohydrate restriction significantly lowers insulin resistance compared to a low fat diet.
9. Insulin levels will drop
High levels of insulin are associated with insulin resistance. Hyperinsulinemia (high levels of insulin in the blood) appears to be an independent risk factor for coronary heart disease. Therefore, lowering insulin levels may be beneficial. Carbohydrate restriction has been shown to significantly decrease insulin levels.
10. C-reactive protein will be reduced
C-reactive protein (CRP) can be measured in blood and is a known marker of inflammation. CRP, in particular high sensitivity CRP (hs-CRP) has been associated with cardiovascular risk. There is evidence that carbohydrate restriction lowers the level of CRP, which may indicate that LCHF diets can reduce inflammation.