If you are like the majority of people and believe your body cannot survive unless you have a plentiful supply of carbohydrates then I have some news for you. You’re wrong, or maybe you’re right or maybe like many you’re just confused. Who couldn’t blame us for not understanding how many carbs we should eat or how much fat and protein is right. So, from my personal experience with some scientific support I’ll give you some food for thought!
For almost two years I have been self-experimenting with nutrition to work out what works best for me. I have submitted myself to countless blood tests and lung function tests in the pursuit of the perfect diet. From high carb – low fat, paleo, low carb – high fat and for the last year a ketogenic diet. I have based my findings on a combination of my experience and science. I think I can safely say I would be one of the only COPD patients, if not the only patient, who tests my bloods daily to see what foods respond positively, or negatively to my disease. I’m also fortunate enough to have the equipment in my home to do this.
Before I go on let’s look at some of the confusion. If we look at the dietary guidelines from western countries, they have similarities in their recommendations. A common theme in the guidelines is a higher concentration of carbohydrates and proteins with a small amount of healthy fats. Why this may work for some people it certainly doesn’t for all. If you dig deep into the research you will find the only two food groups associated with improved lung function are healthy fats as well as certain fruits and vegetables.
The consideration for COPD patients is which types of fats, fruits and vegetables should we eat. All foods have a respiratory quotient. Respiratory quotient is the ratio of carbon dioxide (CO2) produced, to oxygen (o2) consumed, while food is being metabolised. To put it simply, the amount of carbon dioxide produced during eating varies dependant on what you eat. Carbohydrates produce the most CO2 followed by protein, with fats producing the least amount of carbon dioxide. As COPD patients, it’s important to minimise the amount of CO2 our lungs have to exchange and exhale. Many patients with COPD have problems with co2 retention which severely impacts on quality of life. This is where eating to guidelines can be tricky, as many of the recommended foods have high amounts of carbohydrates.
Many dieticians recommend COPD patients should eat whole-grain foods, bran, cereals, pasta and rice. All of these foods have a significant impact on my levels of breathlessness and are foods which I avoid. One world renowned clinic gives a daily food intake for a COPD patient to be 2000 calories with a break up of macronutrients being 69% carbohydrates (356g), 19% protein (100g) and 12% fat (27g).
When you then look at a study on a high carbohydrate v high fat diet, you are left scratching your head. In this study, it is concluded that pulmonary function in COPD patients can be significantly improved with a high-fat (55.1%), low-CHO oral supplement as compared with the traditional high-CHO (60% to 70%) diet. On the recommendations of this particular clinic COPD patients would be left dealing with high levels of co2 in their blood and in my personal experience an increase in breathlessness.
In a 2016 study on malnutrition in COPD patients it was suggested high fat supplements be used to reduce metabolic co2 production, lower respiratory quotient and improve lung function. The authors went on to suggest “in addition, high-fat supplements may be the most efficient means of providing a low-volume, calorie-dense supplement to COPD patients, and may be most beneficial to patients with prolonged mechanical ventilation where hypercapnia and malnutrition are most pronounced”.
My own experience.
I have written extensively about my own nutritional experience, in particular the last year using a ketogenic diet. This diet has consisted of 75% fat, 20% protein and 5% carbohydrates from quality whole foods. Using this formula has correlated to the high fat studies I have referred to in this article. On a ketogenic diet my lung function improved, inflammation markers are suppressed, I had a reduction in the use of my rescue inhaler and my blood panels were excellent.
In my own experience, I have found a correlation between high blood/glucose levels and breathlessness as well as high ketone – low blood/glucose levels and less laboured breathing. While there is some evidence supporting high blood/glucose levels and shortness of breath in COPD patients, more studies are needed to confirm this.
When it comes to nutrition and COPD I have no doubt the one size fits all model does not apply. I also believe guidelines to what patients should eat are confusing and misleading. For any patient looking for dietary advice I would suggest using a dietitian who is not resigned to using one strategy and looks at the science rather than out dated guidelines.
For me, I will continue to eat this way as I have found it a simple and enjoyable way to eat. I understand it will not be for everyone but for those who choose this strategy it gives more firepower to fight this disease. In the coming months, I will be listing a network of dieticians and doctors on my website who are experienced in designing diets for specific diseases.