Weight Loss - fact + fiction
The struggle is real, whether you are fighting with hormones as you age (hands up the over 40’s), trying to beat the genes you’ve been given or becoming overwhelmed with all the contradictory ‘facts’ and an endless list of do’s and don’ts. The worst part of weight management is feeling like you’re battling against something you can’t control.
You’ve got this … with a few simple steps.
With a little bit of science, a guide and some basic habits you can start the journey to a normal weight for you.
I’m not about needless weight loss. Weight loss is about health, loving and trusting your body. It’s about feeling good first thing in the morning and then keeping that sustained energy throughout the day and knowing how to do it day after day after day… What you need is practical steps and scientific evidence.
So lets dive in and break down the weight loss myths that are confusing you.
It is true that we have been sold an oversimplified version of weight loss, as it is rarely as straightforward as calories in < calories out. However, once we understand a few core principles we can make better informed decisions to help us on our weight loss journey.
Do remember though that successful weight loss will at some point require a personalised approach, as there is no ‘one size fits all’ due to the individual variability of our metabolism, genetics, microbiome, and hormonal balance, all of which can require a specifically tailored approach to get the best long-term results.
That doesn’t mean you can’t use these basics to establish better habits and kick start weight loss.
1. Healthy weight loss pattern
It probably won’t surprise you that an extreme, caloric restriction protocol will ultimately not yield the best results. Whilst initially a period of pronounced calorie reduction will reduce body mass (largely due a decrease in body water and muscle glycogen stores) this type of extreme intervention soon plateaus.
This plateau is the result of ‘adaptive thermogenesis’ (1).
This is where the body perceives this deliberate lack of energy as a biologically threatening event. Evolutionarily, food scarcity made it necessary for the body to preserve energy stores during periods of depletion. Therefore, when prolonged moderate calorie restriction occurs, our metabolic system adjusts to reduce energy expenditure whilst increasing our desire to eat.
We can thank alterations in leptin (2) -- one of the hormones that lets us know we feel satisfied and helps to regulate our food intake -- for our insatiable desire to eat when on an extreme diet. This hormone is secreted from our fat cells and signals the brain to stop eating when we are full. However, in rapid weight loss, leptin levels fall quickly and stimulate a big increase in appetite. It is a primitive way of maintaining body weight and preventing starvation.
‘Just about everyone I see in clinic has at one time or another swung between miserable deprivation and binging on their favourite food’. It isn’t fun and fortunately science agrees that extreme caloric restriction isn’t the way to go’.
Therefore, instead of a severe calorie restriction, we can benefit from:
1. A mild caloric restriction over a much longer time - this is much more sustainable and does not trigger the survival adaptation processes which hamper long term weight loss.
2. Limiting the amount of high glycaemic load carbohydrates we eat. These are foods that impact our blood sugar in specific quantities.
—> —> —> When we eat foods that cause a spike in our blood sugar (or even snack all day), insulin is released. Insulin is the key to opening our muscle cells to store the glucose as energy. If our muscle cells constantly have enough glucose stored as glycogen then they reduce the response to insulin. High amounts of circulating insulin lead to the creation of fat and enlargement of our fat cells.
High glycemic load foods = more insulin = more fat storage
3. Instigating a time restricted eating window. There are two ways to do this. One is to eat all your meals in an 8 to 12 hour window and fast for 12 – 16 hours overnight. Two, is to eat three meals (no snacking) at the same time each day, separated by 4-5 hours, and stop eating at least two hours before bed. These approaches help to set a regular pattern for digestion, sleep and eating, leading to a greater weight loss even with the same caloric intake. It also reduces insulin levels (3) improving metabolic health and limiting fat production.
So how might a day following these guidelines look?
Instead of relying on snacks you make sure that your meals are substantial and include:
- Whole complex carbs like oats, salad, vegetables, wild rice, quinoa
- Protein to go with the carbs like yoghurt, tuna, salmon, egg, tofu, beans/legumes
- A homemade dressing with olive oil and maybe some avo on the side and some nuts
and seeds.
- Have a piece of fruit with breakfast and after lunch & dinner. This naturally leads to you
eating a bit less than normal because – hey, no snacking and more real food.
- Stop eating at 7pm and get to sleep at 9-9.30pm.
Done… and it really isn’t too complex.
2. Low carb vs. low fat
Overall, low carb diets appear more beneficial at promoting weight loss than their low-fat counterparts (4). This makes sense. When carbs are eaten, the pancreas releases insulin, in order to signal cells to let in the glucose molecules. When we consume more carbohydrates than we need for energy, storage of glucose is the default setting. As we’ve already discussed, higher levels of insulin increase fat stores and prevent the use of fat for energy.
Therefore, while fat has more calories per gram than carbs, it doesn’t trigger the release of insulin. Therefore, weight gain is not inevitable. You can still overeat fat though as part of a low carb diet and not lose weight. What is significant about low carb dietary protocols is that they actually have sufficient protein. Protein is ultimately satiating (filling) and what our body needs to build all it’s basic structures.
From a health perspective, the complete elimination of carbs is not advised. This would remove a broad range of plant-based fibres and their many benefits (5) to our microbiome, ultimately inhibiting weight loss.
However, a low carb or low glycaemic load approach still allows some of the most beneficial fibre rich foodstuffs. This is especially true when the carbs are consumed as whole complex units without too much interference. This is beneficial in the process of weight loss due to the fact that complex carbs improve blood glucose balance.
Additionally, if we cut back on naturally fat rich items such as avocados, oily fish, walnuts, and olives and olive oil, we risk depletion of essential omega 3 fatty acids. They are necessary for healthy brain cells, hormone production in weight management (6) and reducing our risk of central and peripheral cardiovascular disease (15).
3. Metabolism (+ myths)
Myth – Our metabolic rate is set and cannot be moved.
It’s true there is little variation in metabolic rates from the wilds of remote tribes to the most devoted city dweller. However, it is not the case that we have a ‘unmovable’ set metabolic rate which renders us incapable of weight loss.
Individual variations in metabolism is linked to genetics and epi-genetic alterations (behaviours linked to the expression of our genes). For instance, mothers deprived of calories can lead to children with a predisposition to obesity (7).
It’s also linked to our lifestyle. For example, a greater intake of omega 6 fatty acids promotes a lower metabolic rate, with research indicating it is likely due to inflammation related alterations (8). Excess omega 6 fatty acids are found in foods that contain high amounts of safflower oil, sunflower oil, canola oil, corn and soybean oil – so pretty much every processed food! Natural sources in their original form such as walnuts and pumpkin seeds are healthy.
This means that by increasing our ratio of omega 3 to omega 6 we can encourage a healthier metabolism.
Takeaway -
prioritise avocados, oily fish, walnuts, and olives and olive oil over processed foods containing vegetable oils and find an alternative fat to add to food and cook with such as olive oil, ghee and very small amounts of coconut oil.
Easy!
Similarly, by exercising more we can increase our metabolic rate, showing how flexible and responsive it can be to positive health behaviours.
Interestingly our microbiome also has a role in metabolic processes, at least when we look at animal-based and small scale human studies. When the microbiome of an obese mouse was transplanted into a lean mouse, it too gained significant weight (9). Our gut microbes can influence hormone behaviours, including those of leptin (10)- which directly influences our feelings of fullness or the desire to eat more. Similarly, there is an indication that our basal metabolic rate (the rate at which we ‘burn’ calories at rest) may also be indirectly influenced through microbial signalling (11).
We now know that certain microbiome ‘signatures’ are associated with weight gain; the ‘obese microbiome’ includes higher Firmicutes and lower Bacteroides than lean counterparts (12),- therefore maximising our gut health can be beneficial in our quest to lose weight too.
Q: How do we keep a balance in our Bacteroides: Firmicutes ratio + a healthy ‘lean’ gut microbiome?
A: Higher amounts of plants & vegetable fibres and whole bean/legumes/unprocessed grains compared to animal fats and protein. Your diet can still be omnivore, but plant focussed.
They key is to determine foods that keep your inflammation low, prioritise fibre and are nutrient dense.
4. Protein in weight loss
Protein is not to be feared as part of a weight loss regime. It is an essential part of our dietary intake and provides us with essential and non-essential amino acids necessary for the function of every cell, muscle fibre and as part of key signalling molecules.
Protein also helps us to self-regulate our overall energy intake as we have an internal ‘protein target’- here the body encourages us to eat enough until we meet this protein requirement. If we eat a low protein, processed carb-based diet- we may end up overeating as this target will take longer to meet.
Instead, when we include high quality protein sources, this target is met more readily, triggering the release of satiety hormones in both our gut and our brain (13). The release of these hormones in our gut (from the pancreas specifically) slows the emptying of the stomach into the intestine (16) to maximise nutrient absorption leaving us feeling full for longer and it helps to manage the blood sugar and therefore insulin response. As we’ve already learned, this in turn curbs our appetite and limits weight gain.
However, as with all things, moderation is required. Excess, protein, and protein powders in particular are insulinogenic (14) -- that is, they promote insulin production, and therefore energy storage, which can contribute to weight gain. This is particularly relevant for those consuming protein powders in the absence of moderate exercise and highlights the role of food first approach in reaching protein requirements.
So how much protein do you need?
If you are overweight 1.2-1.6g per kg of body weight is ideal in addition to increasing your general activity and exercise.
Moderately active people require about 1g - 1.4g/kg of protein to maintain healthy weight and muscle mass.
What does this translate to?
For an individual – doing some exercise - weighing about 85kg they’ll need approx. 136g a day for muscle gain and fat loss. This should be spread across three meals.A 70kg active individual will need approx. 112g a day for fat loss and muscle gain.
Want it even simpler?
Have a palm sized portion of protein 3x day. Make sure it is highly available protein. For vegetarians, you’ll need much more plant based protein than a palm sized portion.
Key Takeaways for Weight Management —
Extreme calorie restriction increases our appetite and reduces energy expenditure… so go with a mild calorie restriction by stopping snacking. Couple this with low to moderate low glycaemic load carbs for long term weight loss.
A time restricted eating window can also promote weight loss due to insulin reduction.
Our individual metabolic rate can be positively influenced via exercise, increased omega 3 intake and a healthy microbiome. Increase the plant + veggie based portions of your diet.
Moderate food-based protein intake is essential for health and supports production of our satiety hormones, but, in excess, via protein powders, and in lieu of sufficient exercise, can promote weight gain via increased insulin production.
REFERENCES
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