Low Carbohydrate Diet

Low Carbohydrate Diet

The Facts & The Myths

YOU MIGHT BE ASKING, WHY IS MY CHIROPRACTOR WRITING A BLOG ABOUT DIET?

There is emerging evidence that a diet low in carbohydrates can influence recovery from serious spinal injury and our ability to manage chronic conditions such as arthritis. (1,2) As spine care experts we aim to consistently review new research and introduce best practices to help manage our clients.  In our previous newsletters we have covered a range of specific topics, however in this newsletter the evidence brings us to a more general topic involving dietary advice.A warning: This newsletter may challenge your conventional beliefs about what constitutes a healthy diet!

WHAT IS A LOW CARBOHYDRATE DIET?

The dietary restriction (or exclusion) of foods known to have a high carbohydrate content.  Examples are sugar, bread, pasta, rice, high fructose fruits (pineapple, watermelon, mango), starchy vegetables (potatoes, corn) and legumes (lentils, beans). Most refined foods are very high in carbohydrate.  Common high carb foods that we consume regularly include breakfast cereal, bread, muesli bars, pasta and orange juice.

WHY SHOULD I CONSIDER A LOW CARBOHYDRATE DIET?

In Australia our intake of carbohydrates increased when low-fat dietary recommendations were adopted in the late 1970’s.  Since this time there has been a dramatic increase in chronic debilitating illnesses such as type 2 diabetes, heart disease and Alzheimer’s disease.  There is an increasing body of evidence showing the benefits of a low carbohydrate diet for the management of type 2 diabetes, obesity, atherogenic dyslipidaemia (cholesterol), hypertension and inflammation.

WHAT HAPPENS WHEN WE EAT CARBOHYDRATES?

When we eat, our pancreas releases insulin to move digested sugars into our cells to be later used as energy.  The greater the quantity of carbs eaten, the greater the insulin the body will need to produce to move glucose into our cells.  If carbs exceed the capacity of our cells to store glucose (in the muscles and liver) the excess glucose will be converted to fat and stored in our fat cells.  When excess carbohydrates are consumed over a prolonged period (10-20 plus years) insulin resistance may develop.

This happens when the body must produce ever increasing levels of insulin to control blood sugars.  Excessive insulin (hyperinsulinemia) and higher blood sugars are known factors in the development of the chronic illnesses mentioned earlier.

BUT DON'T WE NEED CARBOHYDRATES TO SURVIVE?

This might come as a surprise, but of the three macronutrients in our diet (protein, fat and carbohydrates), only carbohydrates are non-essential for human life. We cannot function properly for more than a few days without eating fat, and without an adequate protein intake, we develop protein-calorie malnutrition within a few months. But avoiding carbohydrate has no short- or long-term effects on humans, other than the (usually beneficial) effect of weight loss, especially in those who are the most overweight. While we need a constant supply of glucose, it can be produced by the liver from fat and protein and doesn’t need to be ingested as carbohydrate in our diets.

BUT DON'T WE NEED CARBOHYDRATES TO SURVIVE?

This might come as a surprise, but of the three macronutrients in our diet (protein, fat and carbohydrates), only carbohydrates are non-essential for human life. We cannot function properly for more than a few days without eating fat, and without an adequate protein intake, we develop protein-calorie malnutrition within a few months. But avoiding carbohydrate has no short- or long-term effects on humans, other than the (usually beneficial) effect of weight loss, especially in those who are the most overweight. While we need a constant supply of glucose, it can be produced by the liver from fat and protein and doesn’t need to be ingested as carbohydrate in our diets.

IS A LOW CARBOHYDRATE DIET SAFE? SATURATED FATS & HEART DISEASE 

There is concern that increasing saturated fats as part of a low carbohydrate diet increases heart disease.  Here are the results of clinical trials:

  • In the two randomized clinical trials (the highest form of research) that have investigated a low-saturated fat diet versus a high saturated fat diet, there was no difference found regarding heart disease.
  • Three high quality studies in the past 3 years (meta-analyses) found no decrease in heart disease associated with a low saturated fat diet.

ARE THERE DOWNSIDES TO THE DIET?

Low carb can be difficult to follow, particularly when not eating at home.  Most low carb foods are fresh and require regular grocery shopping, and more time is generally required for food preparation.

The first few weeks of a low carb diet can be challenging as our body’s physiology changes.

Sugar, grain and even alcohol addiction can sabotage a low carb diet.

For people with type 1 diabetes, thyroid disorders, multiple sclerosis, or having a history of gall bladder removal, a low carb diet is not prohibited, however consultation with a Doctor who has special training in low carbohydrate diets is recommended.

There is more clinical research to be done regarding the long-term safety of a diet low in carbohydrates.  It is noteworthy however that from the beginnings of our existence, humans predominately consumed low carbohydrate foods.  If our entire human history was compressed into 24 hours, humans have only been eating higher carb foods such as cereals and grains for 5 minutes (the introduction of agriculture) and sugar for 5 seconds. Such a dramatic change in our diet with comparatively little time for our gut and physiology to adapt begs the question, are our ‘balanced’ diets contributing to a rise in chronic disease?

WHAT DOES THIS MEAN FOR ME?
Removing refined foods and returning good fats to your diet is a good start towards a healthier you. Research shows you might even reduce inflammation and improve your healing time! (1,2) For further advice about a low carbohydrate diet, consult your health professional.

RESEARCH PEARL

How reliable are cohort studies regarding what we should and shouldn’t be eating? Diet cohort studies (sometimes called population studies) analyse the diets of a large group of people and attempt to draw conclusions about which foods may be 'associated' with an increase risk of an illness such as heart disease.

A recent comprehensive analysis (meta-analyses) of nutritional cohort studies revealed almost all the foods we commonly eat are significantly associated mortality risk!!(3) Findings such as these have many in the science community questioning the validity of diet cohort studies.

Take Home  Message Next time you see a headline which tells you to avoid a certain food (eg. red meat, fish, eggs or butter) take the advice with a 'grain of salt' unless the findings are based on a randomized clinical trial (preferably more than one).

For a comprehensive list of low carb clinical trials, visit the following: https://blog.virtahealth.com/low-carb-research-comprehensive-list/

1. Strath: The Effect of Low-Carbohydrate and Low-Fat Diets on Pain in Individuals with Knee Osteoarthritis. Pain Medicine

2. Yarar-Fisher: Evaluation of a ketogenic diet for improvement of neurological recovery in individuals with acute spinal cord injury: a pilot, randomized safety and feasibility trial.

3. John P. A. Ioannidis:  The Challenge of Reforming Nutritional Epidemiologic Research JAMA. 2018;320(10):969-970