Welcome to Issue 1 of the Lifestyle & Wellbeing Nutrition newsletter. Each month I will endeavor to dispel food myths and include information that is most often asked during consultations.
It is important to realize that good health is a journey and a discovery whilst making small attainable changes along the way.
There will be backward steps and these are always part of the journey.
In order to learn and realize what is causing the stumbling points, life happens and becomes part of the path to health.
I see so many clients that are confused about the myriad of information on line about diet regimes.. We have forgotton how to eat a balanced meal due to the constant bombardment of fad diets that are generally too hard to maintain.
Do I go for: no carb, low carb, high fat, low fat, full fat whole foods, high protein, vegan, vegetarian, paleo.……..
One of the most confusing aspects of eating is the carbohydrate debate. There is no question that if you have a very poor, high calorie, low nutrient diet that provides an excess energy intake compared to expenditure, the result will be weight gain (7). The weight loss topic is another debate and many studies have attempted to subscribe the perfect diet but unfortunately there has just made the weight loss scenario confusing. Many diets have ensued over the years including low fat/high carbohydrate, paleo, keto, atkins etc. Intensive reviews on the low fat approach have revealed that this does not result in long term weight loss and in fact may have resulted in the obesity epidemic (7). It was certainly believed in the past that if two people of the same body composition were on two identical diets of varying composition but the same calorie count and in energy deficit, they would both lose weight. This has now been disproven as many factors come into play and one of the major players is controlling insulin release and subsequently delaying fat storage. Another player is including protein, as the thermic effect of food (energy required to break down) causes more energy to be burnt and thus there goes some calories that you don’t even realise!
The high fat ketogenic diet, based on low carbohydrate intake, is the latest trend but often not perfect for all. Yes, it is successful for similar reasons as the high protein/ low carbohydrate diets but can be difficult for those who have issues with breaking down fat.
The truth is, there is not one diet that will suit every individual. What works for you may not work for your friend. Influences such as lifestyle, body composition, exercise regime, work commitments, food intolerances, gut microbiome etc., can play a major role in how food is metabolized and utilized.
It is well understood both by individual experience and via scientific studies that severe energy restriction or any diet that restricts whole food health groups are difficult and often non-sustainable (1). A diet program that is sustainable and ensures that biomarkers of ill health decrease should be the goal rather than severe restrictions.
Why we require carbohydrates in our diet
Firstly, when talk about carbohydrates in food this includes veggies, fruit, grains, legumes pasta, bread, cereals and so on. Carbohydrates in all their forms provide fuel for working muscles, cells throughout the body, the central nervous system, brain and the for formation of red blood cells. (2). Carbohydrates are also required to build nonessential amino acids to create proteins for the bodies use. Once carbohydrate is broken down in our stomach, glucose is stored in both the liver and muscle cells throughout the body for further use. The liver has limited capacity to store, so is our small tank (around 100 grams) and any excess consumption is stored throughout muscle cells (dependent on muscle weight but can be up to 500g). When capacity has been reached, that is the fuel tanks are full, there is an overflow to fat cells. Voila, weight gain!
The storage form of glucose is called glycogen. Liver glycogen maintains blood glucose at a set point to ensure the brain and central nervous system are fed. Muscle glycogen is used for exactly that – to fuel muscles when we workout. On very low carbohydrate diets these stores (around 2000 calories) can dwindle as well as liver glycogen stores when we are very active and stores haven’t been replenished between workouts. The body then goes into emergency rations whereby new glucose is made from muscle fibres. One scenario we really don’t want is to break down the muscle we have worked so hard to build!
The point here is very low carbohydrate diets may not be beneficial for those wanting to build or maintain muscle or participating in very high intensity training that utilizes glucose as the main fuel.
Insulin: friend and fo
The hormone insulin is secreted from the pancreas to take up glucose from the blood and store in the liver, muscle cells or fat. Fine so far….. unfortunately as we get older or if we have put on excess weight, the ability to take up sugar and store in muscle declines and we get extra stored as fat. This is often called insulin resistance. Soooo what do we do? Studies have revealed that eating smaller portions of carbohydrate in one sitting can have a great effect on the insulin response. Also eating a meal of lower glycaemic load to release sugar slowly into the blood stream.
Glycaemic index and glycaemic load explained….
Glycaemic index relates to how quickly 50 g of carbohydrate in a certain food is digested and released as glucose into the blood stream. A high GI food raises blood sugars very quickly, pure glucose being ranked at 100 after 2 hours of consumption.
Evidence is mounting that a diet matched for calories but differ in glycaemic index can have an effect on energy expenditure and subsequent weight gain/loss. It is understood that an individual on a high GI diet can have up to a 10% loss in the thermic effect of food and thus a lower energy expenditure when compared to an individual on a low GI diet (7)
Foods that are higher in GI include those which are low fibre, low in good fats and lower in protein such as white bread, potatoes, white short grain rice, processed cakes and biscuits etc.
Low Gi foods include beans, fruit, lentils and grainy bread. They are high in fibre and thus release sugar into the blood slowly and hence less likely to store as fat.
In real life situations we eat these foods combined with other foods containing protein and fat which will have an effect on the response of the sugar being released into the blood stream. For instance if we put avocado on a rice cake, the sugar is released slower.
Low Carbohydrate diets
Recent studies have revealed that low carbohydrate/ low GI diets, combined with high protein have a beneficial effect on body mass, blood lipid profiles and blood sugar profiles. When an individual switches to a low carbohydrate diet and has presented with insulin resistance or metabolic syndrome, cells are encouraged to burn fat as an energy source and thus insulin release is decreased and fat storage also (4). The low fat/high carbohydrate diet that was being held as the miracle cure to the obesity epidemic has been scientifically questioned and in fact may have played a role in poor lipid profiles and metabolic syndrome associated diseases (7). Low carbohydrate diets up regulate fat metabolism and thus initiate weight loss.
Insulin - friend
In my clinic I see many patients who exercise regularly at high intensity or do high- intensity weights and HIIT programs. In order to increase muscle mass and have the energy to complete classes, carbohydrates are necessary. It has been well reported that drinks that consist of protein and carbohydrate post work out, have a number of benefits including glycogen replenishment, muscle anabolism (recovery and rebuilding), and decreasing stress related markers relating to repeated workouts such as hormone loss and inflammation. This is where nutrient timing in a weight loss program becomes paramount to continue weight loss if that is required (5).
Another significant finding is that high protein and very low carbohydrate diets that do not feed for exercise have an influence on RT3 or thyroid hormone levels (6). This hormone is responsible for slowing down the metabolism! And here we have rebound weight gain, even if the diet remains quite healthy……. Frustrating!
Please explain….. so the down low here is to eat carbohydrate around your workout to ensure that muscle is sustained or built upon and on non -exercise days – go low.
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The lifestyle choice that works for you
As mentioned above the aim of a lifestyle change is to be able to be maintained, achievable, retain fat free mass and improve insulin sensitivity to ensure weight loss over an extended period of time. It is very important to reduce
The effect of intermittent energy and carbohydrate restriction on alternating days will keep your metabolism pumping along to ensure continued weight loss without rebound weight gain. It also important that your healthy eating regime is sustainable over the long term. It is not always necessary to drop complete food groups but be smart about choices of food. DO NOT drop your calories so low as to not cover your daily needs over the long term as the consequences can be rebound weight gain and metabolic hormone issues. See a qualified nutritionist or dietician for guidance if required.
References:
1. Harvie.M., Wright,C, Pegington,M. et.al. Daily energy restriction on weight loss and metabolic disease risk markers in overweight. British Journal of Nutrition (2013), 110, 1534–1547
2. Byrd-Bredbenner, C,. Beshgetoor, D. & Berning, j. Wardlaw’s perspectives in Nutrition 8th edition.
3. Galgani, J., Aguirre, C. & Diaz, E. Acute effect of meal glycemic index and glycemic load on blood glucose and insulin responses in humans. Nutrition Journal, 22:5. 2006.
4. Jacobs. P. Nutrient timing with low carbohydrate diets. From International Society of Sports Nutrition: 8th Annual ISSN Conference and Expo Las Vegas, NV, USA. 24-25 June 2011
5. The differential effects of a complex protein drink versus isocaloric carbohydrate drink on performance indices following high-intensity resistance training: a two arm crossover design. Journal of the International Society of Sports Nutrition volume 10, Article number: 31 (2013)
6. Effects of slimming and composition of diets on V02 and thyroid hormones in healthy subjects13 P. Serog,4 M. Apfelbaum,5 N. A utissier,6 F. Baigts,7 L. Brigant,8 and A. Ktorza7
7. Anssi H Manninen . Is a Calorie Really a Calorie? Metabolic Advantage of Low-Carbohydrate Diets. Journal of the International Society of Sports Nutritionvolume 1, Article number: 21 (2004)
8. Michelle Harvie1*, Claire Wright2, Mary Pegington et. Al. The effect of intermittent energy and carbohydrate restriction v . daily energy restriction on weight loss and metabolic disease risk markers in overweight women. British Journal of Nutrition (2013), 110, 1534–1547