Will A Low Carb Diet Work For Weight Loss?

Low Carb Diet for Weight Loss

Will A Low Carb Diet Work For Weight Loss?

Low or no carb (carbohydrate) diets have gained a lot of popularity over the years with a number of well-known ones including Atkins, Keto and Dukan filling our media with promises of weight loss and healthier lives. The premise that ‘low carb’ or ‘no carb’ is the answer or even the secret to weight loss though just simply isn’t true.

What is a low or no carb diet and where did they start?

Low carb diets promote a reduction in the intake of carbohydrates from foods such as pasta, rice and breads but also starchy fruits and vegetables and legumes.

Most people believe that the Atkins diet was the ‘original’ low/no carb diet. Dr Robert Atkins was an American doctor who was an overweight man weighing 100kg (15.7 stones) when setting up his cardiology  practice in New York in 1963. He had attempted many ways to lose weight with no success before trying the low carb approach. When doing this he managed to lose weight without counting calories and so used this ‘diet’ with his patients to support their weight loss too. By 1965 he’d appeared on the Tonight Show, was in Vogue magazine in 1970 and published his original book Dr Atkins’ Diet Revolution which became one of the best selling diet books of all time.

The Atkins diet was not the first low or no carb diet and in fact he never really claimed it was. In fact it was even written about back as far as 1825 when Jen Anthelme Brillat-Savarin talked about the link between obesity and carbohydrates.

At the same time as the Atkins diet rose to fame there was also another doctor doing something very similar. Dr Irwin Stillman wrote The Doctor’s Quick Weight Loss Diet in 1967 which sold 2.5 million copies promoting a diet that was high in protein and low in carbohydrates. This was because protein takes more energy to metabolise and so could cause greater weight loss. Dr Stillman lost 50lbs following this diet himself and reportedly treated over 10,000 patients with it.

These diets weren’t without controversy at the time though, and although Dr Atkins claimed his diet kept hunger levels low by reducing insulin levels and therefore would lead to weight loss the American Medical Association’s Council on Foods and Nutrition attacked his claims stating that the high fat content of his diet would lead to cardiovascular events such as heart attacks and strokes.

Many doctors at the time thought of the low carb diets simply as fads and organisations such as The American Heart Association still pushed the notion that low fat diets were best, despite those being proven to fail on many occasions.  Despite this backlash to the low carb diets they still prevailed with the wider population with support from the media and it is said that in 2004 there were more than 26 million Americans on some form of a low carb diet.

Over time more and more scientific evidence began to back the low carb diets showing that they did see greater short-term weight loss. Not only that but in a number of studies the Atkins style diet was also shown to lower average blood sugar levels, reduce the overall number of calories consumed each day and also lower insulin levels and restore insulin sensitivity, which is why this is often a popular diet with diabetics.

However, since it’s surge in the early 2000’s the Atkins diet has seen a big decline in popularity. A lot of the reason for this is covered below when we look at why low carb diets don’t work.

Atkins Diet Book

Why do low or no carb diets work?

One of the main reasons low carb diets can work is that they lower insulin levels. Insulin is the hormone that regulates our blood sugar levels and it when we have high levels of insulin it is linked to fat storage. There are some claims that when insulin levels go down from carbohydrate restriction the fat in cells is freed from cells and becomes accessible for the body to use as energy, however, this isn’t necessarily true. Although the link between high insulin and obesity is there but the mechanisms as to why are still debated, but it is acknowledged that lowering insulin levels is beneficial.

One of the key reasons low carb diets work is that they automatically increase the amount of protein you eat as you look for foods to replace the missing carbohydrates. Having an increase in protein can reduce your appetite and keep you feeling fuller for longer whilst removing cravings for sweet foods and can possibly boost your metabolism, especially if done alongside an exercise regime including strength training. Most nutritionists believe that the high protein content of the low or no carb diets is the main reason for their effectiveness.

The other reason for success is that by removing carbohydrates you are automatically removing what we all know are some of the unhealthiest foods such as sugary drinks, pizzas, chips, pastries, cakes etc. Now, no one would argue that removing these foods from your diet is a bad thing, but do we need to remove all carbohydrates? What about the ones we get from vegetables, pulses, wholegrains etc? 

Finally, the other reason for success is that by removing a number of these unhealthier foods as well as other carbohydrates generally means there is a reduction in overall calories consumed, although this is also often seen on low fat diets. By going on a ‘diet’ the exclusion of foods and therefore the general lowering of calorie intake will often have weight loss benefits, in the short term at least.

Why don’t low or no carb diets work?

Low carb diets have been shown to lead to weight loss, but this is generally at the start of the diet. Now this weight loss can be for other reasons and not actually fat loss. When the body receives its energy from carbohydrates, it receives it in the form of glucose, which is then converted to glycogen to be stored for later. When this happens it is stored along with water molecules which it needs to reconvert it back to glucose later. When someone is on a low carb diet they make les glycogen stores and therefore hold less water and it is this reduction in water that is often confused for fat loss.

Although there is evidence to show that people lose weight initially on low carb diets (especially the Keto diet) most research shows that this is not sustained in the long term.  There is often a high drop out rate as people can’t stick to the restrictions of such a diet.  People may also get other symptoms when they cut out of restrict carbohydrate intake suddenly and these can include headaches, fatigue, low mood, and food cravings as well as digestive issues such as constipation which is caused by the removal of fibre from the diet. Fibre is an essential part of the diet and something most people already don’t get enough of. It is stated that most people should get 30g of fibre a day, however, the majority of people even on a standard western diet and before removing carbs only get around 18g a day.

When we remove a food group like carbohydrates from the diet this can lead to nutritional deficiencies. The Keto diet also restricts many fruits and vegetables and so means if people are on this diet long term then they are likely to be missing out on the benefits of nourishing their gut bacteria and getting the variety of vitamins, mineral and other nutrients from a wide selection of fruits and vegetables.

Restricting a macronutrient like carbohydrates also means we have to fill that gap in our diets with the others of protein and fat. Now these macronutrients in a balanced diet are again essential for the body to function at it’s best, however, when consumed in excess can cause problems.

Increasing the amount of protein and fat we eat can help us feel fuller and reduce our hunger, which supports the weight loss as few calories are consumed overall, however, they can also lead to other health conditions such as higher cholesterol, kidney problems and bone issues if following this style of diet for a prolonged period.

Cholesterol can be increased when people increase their dietary fat, but don’t differentiate between saturated and unsaturated fat. Some studies have shown up to  a 44% increase in LDL cholesterol (‘bad’ cholesterol) among healthy young people following a low carb diet. An increase in this type of cholesterol can then increase the risk of heart disease and strokes.

Its an increase in dietary protein, which is proposed on the Atkins diet which can lead to kidneys and bone issues. If anyone has an underlying mild kidney problem, which they may not even be aware of, then an excess in protein could cause problems. The by-products of protein are harder for the body to breakdown and so can get stored as waste which increases the pressure on the kidneys to filter this out.  There is also some research which suggests that protein is acidic, and when consumed in high amounts needs to be neutralised, and this process of neutralising it requires calcium which is then released from the bones.

scales for weight loss

So what is the best way to lose weight?

The best way to lose weight is not to think about a specific diet which removes certain foods from your diet such as taking out fats or carbohydrates altogether but to think more about balance.

You can lose weight, gain energy, and even help other symptoms your body might be struggling with by following a more balanced diet that will work, not just for the next few weeks but for life. While instant results are always appealing, they are rarely sustainable. What you want to achieve is steady weight loss, week after week, until you reach your goal.

The way of eating that seems to work best for most people is following a low GL ‘diet’ and this means you don’t cut out carbohydrates altogether but make smarter choices about the ones you do eat. This way you never feel hungry, you still enjoy food, it’s safe, it’s easy to do and you’ll feel great.

There are 5 core principals to follow aside from thinking about the carbohydrates and low GL and these principals apply to anyone wanting to lead a healthier life and just applicable to those wanting to lose weight.


Eat like a Mediterranean

The Mediterranean way of eating is known to have potent anti-inflammatory effects on the body and inflammation is widely known as the precursor to many chronic diseases and autoimmune conditions such as arthritis, Alzheimer’s, heart disease and hypothyroidism. The Mediterranean way has a strong focus on vegetables, fruit, legumes (lentils, chickpeas, peas, and beans), grains, olive oil, nuts and seeds, herbs and spices, alongside some fish and seafood, moderate dairy and a limited amount of meat.  Mediterranean’s also eat their food as part of a wider community, with friends and family which is now increasingly being linked with better health and longevity so think about that the next time you’re bolting down a sandwich over your laptop at work.


Pack in the Protein

Protein really is one of the most important elements of our diet. If you do nothing else take away the notion that protein needs to be the star of the show for all your meals. Protein is literally the building blocks of life. It is necessary for every cell in our body from hormones, bones and DNA to skin, hair and nails. We just can’t function without it. We need it for energy production, sleep, mood and libido. It is also great at keeping us feeling full for longer and curbing cravings. So protein really ticks a lot of boxes.

On average you want to be eating about 1g of protein per kg of bodyweight and more if you exercise regularly. You need your protein sources to be ‘complete’ to get all the benefit from them. Vegetarian sources generally aren’t complete and so it is more important to combine different sources and eat variety.

Complete sources of protein include: meat, fish, dairy, eggs, quinoa, soya, buckwheat, seitan, tempeh, tofu, edamame beans, nutritional yeast

Almost complete: hemp and chia

Incomplete sources: beans, lentils, chickpeas, nuts, butters, seeds, brown/black/wild rice, rye, wheat, spelt, oats and barley


Don’t Fear Fats

Fats have been vilified over the years and it was often said the only way to lose weight was to go low fat (just look at slimming world) but it’s simply not true. The fact is we need certain fats in our diet. Our hormones are made from the cholesterol in fat, our brains are 60% fat and fats are also needed to make cell walls, protect our brain neurons and even to be able to absorb the vitamins A, D, E and K.

A balanced meal should always include some fats – some avocado, a small handful of nuts, a spoon of olive oil or oily fish. Now these are all unsaturated fats which are shown to have beneficial effects on our health. These contain omega 3’s which have anti-inflammatory effects. Whereas saturated fats like butter, coconut oil, red meat or cheese contain more omega 6. Omega 6 in large amounts is actually pro-inflammatory (so the complete opposite of the Omega 3’s in unsaturated fats). If you don’t eat two portions of oily fish a week then it is advisable to supplement with omega 3.

One thing that has no disagreement is that trans fats are bad for heart health. These are found in margarines and doughnuts and can often be found in takeaways and fast foods.


Get enough Fibre

Fibre is known to benefit us by lowering cholesterol, avoiding constipation, slowing the release of glucose into the bloodstream and helping us feel full. It is recommended that we get 30g of fibre a day, however, most people only get around 18g a day.

There are two types of fibre, soluble fibre in the form of oats and fruit and insoluble fibre from things like wholegrains, nuts and seeds. Soluble fibre helps things pass through the digestive system and feeds our good bacteria while insoluble fibre provides the bulk and makes it easier to pass a stool. Fibre also helps fill us up for longer along with protein, helping to reduce the cravings and need to snack between meals.  Easy ways to increase fibre include:

  • Keep the skin on fruit and vegetables
  • Add 2 tablespoons of ground flaxseed to meals e.g. porridge or salads
  • Add lentils, beans and chickpeas to soups, stews, curries
  • Choose wholewheat
  • Choose fibre dense fruits: pear, figs, kiwi, raspberries, blackberries, apples

Drink enough water

It’s almost impossible to find even one system in the body that doesn’t require water.  Water enables the circulatory system to deliver essential oxygen and nutrients to the cells all around the body, it allows the kidneys to filter out waste products, it helps us to sweat and cool off when we’re too hot, and it helps our digestive system too, just to name a few functions. 75% of the brain is made up of water so it makes water crucial in regulating mood, productivity and concentration.

We should all be aiming to drink at least 1.5-2l of water a day, with an average mug or glass holding around 200ml that’s 8-10 glasses a day. 

One tip to keep an eye on your intake and make sure you are getting enough is to get a BPA free water bottle that you know how much is in it, so if it is a 1 litre bottle you know you want to drink 2 a day.

Although tea and coffee will provide the liquid, the other ingredients such as caffeine can have a slight diuretic effect (causes the kidneys to produce more urine to get rid of extra fluid) on your body so you are best to stay away from these or at least reduce consumption.  You really don’t want to be having caffeine after midday as it takes a long time to leave your system and if you have caffeine at midday there will still be about ¼ of this in your system at 10pm-midnight. The best way to hydrate really is to simply drink water.

So what about the carbohydrates?

 Well to understand what to really do with carbohydrates we first have to understand how our body works and processes them. The body is designed to burn glucose for energy which is then carried to the cells by the bloodstream. The glucose comes from the breakdown of carbohydrates such as grains and fruit as well as the obvious sugars. In todays modern world most people are eating too many carbohydrates, and especially refined ones which break down quickly. This means we end up with more blood glucose than we need. The body knows it can’t leave the excess glucose in the bloodstream as it damages the arteries so it sends it to the liver to be converted to fat and stored for another day when we might need it, but that day never comes, so it stays in our bodies as fat.

There are certain carbohydrates known as ‘refined’ which raise the blood glucose levels very high and it is these that we need to remove and focus on the more complex carbohydrates which are the ones that take longer to break down to glucose and so don’t spike our blood glucose levels as much.

All foods can be given a GL (Glycaemic Load) score which takes both the quality and quantity of the carbohydrate into account (and is different from GI or glycaemic index). Foods with a higher GL can lead to weight gain if we eat too much of them.

Low GL foods are good because the glucose is released into the bloodstream slowly, and blood sugar therefore remains stable. This is important because keeping blood sugar steady prevents the energy slumps that trigger cravings. It means your body can use the glucose at the same rate it is released ( or faster) and so none is left over to be stored as fat.

Examples of low GL foods include: oatcakes, wholemeal bread, baked beans, wholemeal pasta, all vegetables (except potatoes and parsnips), fish, white meat, eggs, soya products, milk

Medium GL foods are healthy in moderation. They release glucose into the bloodstream at a slower rate than high GL foods, but still raise blood sugar to a level where it is more likely to over produce glucose, and some will still be turned into fat. For losing weight these should be limited and eaten alongside low GL foods

Examples of medium GL foods include: rye crispbread, rice noodles, parsnips, boiled potatoes, bananas, rice milk

High GL foods are to be avoided because they release glucose into the bloodstream fast, and raise blood sugar levels too quickly for the body to cope. The body can’t process all the glucose and so deposits a large proportion for storage as fat. Your blood sugar can then crash causing cravings.

Examples of high GL foods include: white baguette, muffins, cornflakes, all rice (except for brown basmati) couscous, puffed-rice cakes, all potatoes (except boiled), honey

So in summary the best way to lose weight is to eat a Mediterranean style diet with plenty of protein and fibre, make sure you include healthy fats and swap out your refined high GL carbohydrates for low GL ones to ensure your blood sugar is balanced throughout the day without the spikes and the need for the body to convert excess glucose into fat.

If you would like to know how Helen could help you with a personalised plan to support you on your weight loss journey then get in touch via the website at Helen Jane Nutrition

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