As far as popular ideas and diet crazes go, Intermittent fasting is right up there with this year’s new “IN” thing in the diet and lifestyle world "keto". Not surprisingly they are promoted hand in hand.
Now let me be very clear here, when I refer to "KETO" I am referring to the mass-popularity diet craze that is able to be googled and followed in a cookie cutter/generic forma, there are even cheeky untrained people trying to package traditional Keto as modified for Bariatric patients, when I am yet to find an example that actually delivers to the needs of its clientele (or is delivered by actual health/nutrition professionals) that's why I don't call my programs "KETO".
I'm not saying that a diet that promotes ketosis is not achievable for Bariatric folk, in fact that is EXACTLY what I advocate for the majority of my clientele, what I am saying is, that it 100% has to be balanced for the individual and modified to suit (and this HAS to be done by a Nutritionist, seriously we KNOW what we are doing.)
So for the sake of argument and to save confusion "KETO"(mainstream) is a NO-NO, BUT Nutritional Ketosis (what I do) ,... is the way to go-sis !
What is intermittent fasting? It is the process of intentionally limiting the ‘window’ in which you intake your daily meals thereby reducing overall intake and potentially allowing more time for the body to do non-digestion related biological processes of DNA synthesis and repair.
What is Keto? This refers to the mainstream ketogenic diet that is very popular right now, which emphasises very little carbohydrate intake (in many cases under 30g per day) , moderate protein intake and high fat intake, which are calculated based on your caloric intake based on percentages of around 25-35% Protein and 50-60% Fats *For non-bariatric individuals; in order to push the body into a ketogenic state (which is the utilisation of fat metabolism for fuel(ketones) instead of glucose/carbohydrate metabolism).
Whilst low carbohydrate diets and intermittent fasting in and of themselves can be beneficial for some people with fully-functioning and untouched gastrointestinal tracts; Those who have had bariatric surgeries such as VSG (vertical Sleeve Gastrectomy), RNY (Roux En Y Gastric Bypass ) or DS (Duodenal Switch) as well as the many other variations of the same procedures; those individuals should demonstrate extreme caution when embarking on practices that :
A) Restricts or removes, eliminates or deprives or imbalances the intake of any one food group.
B) Restricts or removes, eliminates or deprives or limits the opportunity or ability to take in vital nutrition.
What does this mean, and why is it different for post-op Bariatric patients?
1. Physical Capacity- You're not the same as you used to be.
Pretty self-explanatory this one, bariatric surgery reduces your food intake capacity. For RNY your stomach pouch becomes the size of a golf ball and for VSG the size of a small banana. Therefore, it is imperative that the use of that space is considered with the highest level of importance.
Diets such as the widely popular keto diet that advocate extreme restriction of carbohydrate, replacing it with fats and proteins predominantly derived from animal sources, do not offer your stomach the variety it requires to supply your body with its essential nutrition.
It’s a no brainer really, should you fill up on one food group only? or Should you balance your meals to incorporate all food groups and offer your body a better opportunity to nourish and heal itself?
2. Malabsorption : Nutrient and Nutrition requirements
The majority of mainstream Bariatric procedures are malabsorptive surgeries, meaning that they diminish the capacity or ability of the digestive system to breakdown, assimilate and absorb nutrition.
How does this happen?
VSG removed up to 80% of the patient’s stomach, and with it up to 80% of the stomach surface area responsible for the stimulation and excretion of digestive enzymes, the break down and absorption of proteins and enzymes and the absorption of nutrients; its expected that deficiencies will occur without constant monitoring of nutrition.
With RNY the stomach and small intestines are re-routed to bypass the first third of the small intestine which is where the majority of our vitamin and mineral absorption takes place. Together with this, the stomach itself is bypassed and therefore is not exposed to what we eat at all, so it does ZERO absorptive processes. This can lead to widespread vitamin and mineral deficiencies, hormonal dysregulation, GUT dysbiosis, impact thyroid, mental health, energy production, immune and inflammatory responses… just to name a few.
I think that it is also important to add here that Low-Carbohydrate diets that are high in animal derived fats and proteins are associated with higher rates of mortality as oppose to moderate-low carbohydrate diets with higher plant-based proteins and fats.
So, this is where I will begin to sound repetitive, but it is essential to the message:
Restricting or removing, limiting or omitting is increasing the level of deficiency related to your surgeries.
Calories signify ENERGY not NUTRITION. Macros (Macronutrients) reflect the true nutritive potential of your foods.
The ratios to which you consume these macros (Protein, Carbohydrate and Fat) can either enhance or diminish weight loss potential, wellbeing potential and potentially exacerbate or diminish health conditions.
Getting the right amount of proteins carbs and fats (as well as fluids, fibre and nutrients) are important for
•Immune system health
• Your actual Ability to digest food and absorb nutrients
•Cellular structure and function
• Maintaining or enhancing your Body composition (your lean body mass and body fat)
And those are just a few…
3. Hormone Control
The stimulation, production, transference, utilisation and depletion of your hormones, transmitters, enzymes and proteins; not only rely on what we eat for their processes but are vastly influenced by what we eat in the manner in which these processes are performed.
Some beautiful examples of these are Thyroid hormone, Cortisol and Serotonin.
Thyroid hormone requires the presence of insulin to convert inactive T3 to Active T4. Carbohydrate being glucose rich, illicit the required insulin response, proteins illicit a small insulin response and fats do not illicit an insulin response at all. Therefore, diets that restrict carbohydrate to extreme levels do not support those with impaired thyroid function; a comorbidity common amongst those who have had bariatric surgery.
Cortisol is released in response to stress in our ‘fight or flight’, it also aids in the regulation of the circadian rhythm (sleep/wake cycles), influences hunger and satiety and its production is also stimulated by… yes you guessed it Carbohydrate.
Serotonin bet you can guess where I am going with this one. Serotonin production is stimulated in the intestine by metabolites secreted by bacteria that eat… carbohydrate !
Now, I think it is important to just briefly touch on something here (as it is deserving of a blog post all of its own) , how many post-op bariatric patients are:
Your diet may (probably is) be to blame.
4. Starvation Mode: Metabolic Resistance
Again, this one should be a no-brainer, but let’s recap the important points so far.
So, you can only eat so much in one sitting, but your metabolic needs remain the SAME AS ANY NON-WEIGHTLOSS SURGERY PERSON.
So, you need to give yourself the opportunity to take in what you need. Limiting further calories is not the answer to ongoing weight loss, you need to improve your metabolism by increasing calories in conjunction with output to a level of maintenance.
For most successful people 2 years + post-op this is around 1400 calories minimum and more if exercise is in the picture. If you are eating under 1000 calories per day and are more than 9 months post-op. You are starving yourself.
Starvation is one of the main contributors to post-surgical hair-loss, mental decline, depression and stalls/plateaus in weight loss outcomes.
Common arguments in the keto + Intermittent fasting circles are:
For you to intake sufficient nutrition whilst meeting your goals, your macros need to be calculated to not only support weight loss, but support hormone regulation, provide well balanced nutrition and not be excessive in any one area (this is the problem with mainstream keto )… if you overdo one, you are under consuming another, which poses a few health dilemma for those who have had bariatric surgery.
Because you want to:
• Continue losing weight but bolster and boost health and wellbeing.
• Avoid starvation mode and starvation related fatigue.
• Avoid starvation related hair loss and nutrient deficiency.
• You want to feel satisfied but not regain.
We have to get out of that dieters mindset.
There are no evil macronutrients…
Carbs are your friends, they help with hormone regulation, they speed up muscle recovery/repair, and EVERYONES CARB NEEDS WILL DIFFER dependant on activity level, life stage, medical conditions and goals; and extreme calorie restriction is dangerous and will in the long term hurt your efforts.
There is a delicate balance between your caloric intake and macro ratio... both are just as important as the other. Your carbs and protein might be on point, BUT you can still overeat your needed calories. As well as under eat them. And I'll tell you now, that’s why you are stalling..
• Not having enough fats in your diet could lead to hormone issues, increased cholesterol, dry or irritable skin conditions, hair fall and poor immune responses and mental health issues.
• Not having enough carbs in your diet will lead to sluggish workouts. lethargy, foggy brain, and moodiness, hormone issues, mental health issues, poor sleep, unrested sleep, poor stress management.
• Not enough protein in your diet will cause your body to start using muscle as energy, poor healing, depressed immune function…
And again those are just a few examples... we would be here all day.
5. Disordered Eating and Poor Food Relationships
You have to sit back and think, “what lead me to the operating table to begin with” , whilst there are a lot of people with medical conditions that make the gaining of weight a very easy process; the vast majority of post-op bariatric patients will agree that it is their eating styles and poor food behaviours that were the reason behind the unhappy rollercoaster ride.
The average weight loss surgery patient has spent the majority of their life on a ‘diet’ and has a good understanding of nutrition as a baseline as they have “tried every diet known to man”: this has then facilitated the cementing of disordered and restrictive food behaviours. Which ALWAYS lead to binge actions.
Because restriction and deprivation lead to physical and mental starvation.
Intermittent fasting and Keto: One restricts your time and the other restricts your variety and choice. Observationally, ‘falling off the Keto-Wagon’ is an all too common occurrence, proving that it is just another diet that feels restrictive an unnatural to so many.
I really want to drive something home here.
The largest influencing factor behind obesity and the need to undergo bariatric surgery stems from food related mental health, and therefore it is important to really consider the impact not only physically, but also mentally.
Adopting further deprivation-centric or restrictive food practices will inevitably lead to feelings of guilt, shame and failure when the diet cannot be sustained.
We must seek balance, stability and joy in our food and in our lives.
One final, and very important issue that needs to be addressed is:
Ketogenic Diets + Bariatric Surgery + Alcohol Consumption
Bariatric Patients tend to exhibit higher blood alcohol concentrations after relatively small amounts of alcohol consumed, which put strain on the liver.
Caloric restriction (as seen in Bariatric Surgery and Fasting)greatly impacts the livers ability to clear and remove toxic substances such as alcohol from our blood stream.
So to begin with our liver is doubly UNDER STRAIN... then we add KETO...
Ketone bodies (the byproduct of the ketogenic process) impact the ethanol metabolising system(an alcohol clearance system regulated by the liver) and increases that potential for liver damage exponentially. It can also make people more sensitive to toxic exposures and sensitive to chemical agents, cleaning products, air pollutants and solvents, and even some medications.
It is always important to have ALL the facts about what a particular dietary model could do to your health rather than just focussing on the potential weight loss.
Weight loss IS NOT everything, LIFE is EVERYTHING.
Please consider your health and get your own individual Balanced Macros.
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Mental nutrition is BioME Integrative Nutrition's
Own Health and
Wellness Blog. Covering all things from what goes in to what comes out after Bariatric Surgery and beyond.
Carrie Ross: Clinical Nutritionist | BSc Nutritional and Dietetic Medicine | Nutritional/ food Behaviour Counselor |Bariatric Health Coach | Social Trainer |Author