Low Carb Diets: Do they Work?

It is hard to mention the word ‘diet’ these days without thinking of the low-carb diet. Indeed, there are quite a few around now.

This article examines both weight loss and the risks and benefits of the low carb diet. Here are just a few of the most popular low -carb diets:-

In fact, the low carb diet has never really gone out of fashion and medical researchers have argued the risks and benefits for over three decades.

The whole concept of the low-carb or keto diet is complicated. There are many variations on the theme, with some low carb diets having a higher fat content. Furthermore, the amount of carbs permitted in the various low carb diets varies considerably.

I’m on one of those low-carb diets. Whenever I feel low I eat carbs!

Low Carb Diet Weight Loss

Well, the basic principle underlying the low carb diet is exactly what it says on the tin; eating fewer carbs will lead to weight loss. Furthermore, eating a lot of of carbohydrates in the diet will lead to weight gain.

However, the basic principle of weight gain is when more calories (or energy) are taken in to the body than are used. In some ways, it is irrelevant whether these calories come from carbs, fats, sugars or protein sources.

The Doc says that eating whole foods helps to improve health. So, I’m going to start with eating this whole donut.

Carbohydrates seem to have become the ‘nutrient non-grata’ over the past few years. However, carbohydrates are a very important part of any healthy diet and essential for providing energy to the body’s organs, brain and blood cells. Indeed, to prevent chronic disease and provide the daily nutritional needs and energy intake the Institute of Medicine recommends that :-

A Bit more about Carbohydrates

Carbohydrates should make up 45% to 65% (at least 130g of carbs per day) of the total calorie intake and
Fats 20% to 35%
Proteins – 10% to 35%

However, the Institue of Medicine also adds that because carbs, fats and proteins are all energy sources they can be substituted for one another quite easily. Hence, the above recommendations are a useful and flexible dietary guide only.

Also, it must be remembered that the above dietary recommendations were from a research paper in 2002, which is almost 16 years ago. Indeed, a lot more research has gone under the bridge since then.

Oh! It’s not fair Moose.
I only want two things in this life, to lose weight and to eat.

I only really want to do one and that is to eat donuts.

How Many Carbs is Low-Carb?

The low carb diets, still popular today, vary as to the amount of carbohydrates allowed together with the amount of fats and proteins.

The original version of the Atkins diet, for example, allowed unlimited amounts of protein and high-fat foods and a very low carb intake.

So, bearing in mind that the Guideline Daily Amount (or RI) of Carbohydrates per day is about 230g let’s take a look at some of our popular low-carb diets :-

The Atkins Diet : 20g to 70g of carbs per day (depending on the phase)
Keto Diet : Each individual person’s allowance is different, but the aim is to enter ketoacidosis. General guidelines suggest around 35g of carbs per day.
The Paleo Diet : <50g to 150g of carbs (although no set amount of carbs, for maximum weight loss under 50g is recommended.
The South Beach Diet: Around 50g to 140g of carbs per day based on a 2,000 calorie intake and depending on the phase.
The Military Diet : Around 68g to 110g of carbs per day
Dukan Diet : Low Carb diet but no official restriction of carbs

Wow! There are quite a few to choose from. If you were ever insane enough to give up donuts how do you know which to choose?

Low-Carb Diets are Quite Similar

Actually when you compare some of the above diets, they are all very similar. Just varying themes on the same basic principles. Most suggest starting off at around 20g to 50g of carbohydrates daily, but gradually, over the weeks or ‘phases’ the amount of daily carbs increases.

However, in comparison to the 230g recommended daily amount of carbs by the Institute of Medicine there are times when these diets are woefully low in carb content.

I agree. The best thing these people on the low-carb diet can do is eat a donut!

No Moose! That’s not quite where we are going with this

Do Low-Carbs Diets lead to Weight Loss in the Long Term?

Basically, any diet that reduces caloric intake will lead to weight loss. However, the main question here is, whether or not a low-carb diet is more effective and healthy for long term weight loss than alternatives.

A lot of the popular diets have a VERY low carbohydrate intake in the early or initial phases of the weight loss plan. Indeed , there is not a lot of medical research that is in agreement regarding the pros and cons of the low-carb diet.

What’s the bottom line then doc?

Well, I will say what I always say.
I believe that a more healthy approach is a healthy long term eating plan that includes ALL the food groups.

Factors Affecting Weight Loss from Diets

As we can see, there are also many other factors that will affect weight loss and reduce the risk for some chronic illnesses. Here are just a few factors:-

the length of the diet
the metabolic rate of the individual dieting
the individual health of the person on the diet: For example, some health complaints such as Cushing’s syndrome, diabetes and hypothyroidism can all lead to weight gain
medications: Some medications, such as anti-depressants can lead to weight loss
the number of calories per day
amount of daily/weekly activity
the number of other nutrients allowed on the eating plan such as the ratio of fat and protein
food choices after the low-carbohydrate diet ends
quality and quantity of sleep

So, even though we are going to have a look at some of the medical research surrounding low carb diet weight loss, it is important to remember that each person is different. Hence, we suggest that if you do have money to invest on weight loss, than an individual eating plan for life, put together with a nutritionist, is the way forward.

A lot of people don’t have money to invest in private nutritionists and individual eating plans.

I know that. However, you can visit your physician for a check up and then start a healthy eating plan, such as the Mediterrnenan Diet or the Dash Diet

Low Carb Diet Weight Loss Research

So, let’s take a look at some of the medical research regarding the low-carb diet and weight loss.

Firstly, let’s look at a positive review for long-term weight loss following a low-carb diet. One 2013 medical study examines thirteen very-low carbohydrate ketogenic diet (VLCKD) on long-term weight loss in obese patients. The very low-carb diet is defined here as less than 50g per day.

Specialists compare weight loss and cardiovascular risk of the VLCKD to that of patients on a more traditional low-fat diet (LFD). That is less than 30% of calories from fat sources.

This research study concludes that:-

“Individuals assigned to a VLCKD achieve a greater weight loss than those assigned to a LFD in the long-term. Hence, a VLCKD may be an alternative tool against obesity.”

So, that’s it then. A low-carb diet leads to weight loss in the long term. Right Doc?

Oh Moose! It is never that simple. Here is a research study suggesting that low-carbs diet lead to long-term weight gain.

Is Weight Loss on the Low-Carb diet really the Point?

The ‘Good’ Carbs (or whole carbohydrates)

We believe that the main question is whether or not a very low-carb diet is a healthy, sustainable eating plan. The answer has to be a big fat NO.

Consuming very low amounts of carbohydrates, or cutting out any food group almost completely, is not nutritionally sound and does not make up a rounded well-balanced diet.

Furthermore, it is essential to know the good carbohydrates, that are essential for well being, such as:-

Barley and Buckwheat
Lentils, chick peas, green peas and beans
Oatmeal
Fruits: Such as bananas, cherries, apples, blueberries
Vegetables: sweet potatoes, broccoli, spinach

So ALL carbohydrates are NOT foods from the Prince of Darkness, after all ?

No, Moose. Natural carbohydrates like whole grains, fruit and veg and beans are all essential and beneficial to our health. It is the bad (or refined) carbs that are the problem.

The ‘Bad’ Carbs (or Refined Carbs)

This is where we think that there has been great confusion with the low-carb diets. If you cut out refined carbohydrates that are not good for health at all, you will lose weight (and reduce your risk for chronic illness).

However, why cut out fruit, veg, whole grain and beans too, that are full of essential vitamins and minerals and fibre?

Quite simply any carbs that are processed should be avoided at all costs. Such carbs are low in nutritional value and high in calories. Furthermore refined carbs cause spikes in insulin levels.

Come on then Doc. What can’t we eat?

Examples of Refined Carbohydrates

Some Examples of refined carbohydrates include:-

Refined Breakfast Cereals
White Bread
Pizza Base (White)
Pasta (White)
Chips
Fries
Pretzels
White Flour and everything made from it like donuts, cakes and cookies
Fruit Juice, Soda and any sweetened Drinks
Sweeteners
White Pizza Base

So, basically we can just cut out the above carbs and eat the healthy ones.

Instead of the total low-carb diet?

Yes. Simply cutting out the ‘white’ carbs will lead to weight loss and improve health.

What is the Theory Behind the Low-Carb Diet?

There is no question that low-carb diets lead to successful short-term weight loss. Indeed, numerous medical studies have verified this.

Because the body usually uses carbs as an energy source, when the carb intake is reduced the body changes and uses the stored fat supplies as energy instead. Hence, the weight loss on these diets.

When the body breaks down stored fats to use as energy the body produces ketones. This is why low-carb diets are also often known as ketogenic diets.

So, what are the pros and cons of a low-carb diet doc?

Well, let’s have a look then.

The Good News or Positive Research

Experts can not agree on the benefits of a low-carb diet long-term. Indeed, medical studies are few and far between and there is not a lot of data over the long-term.

However, some research suggests that the short term benefits are as follows :-

Weight loss and a decrease in Body Mass Index (BMI)
Decreases triglycerides (fat or lipid in the blood that can cause cardiovascular disease).
Lowers the ‘bad’ cholesterol and raises the ‘good’ cholesterol level
Lowers blood sugar levels
Improves metabolic syndrome
Improves insulin resistance
Improves Type II diabetes

Well, that doesn’t sound too bad.

Yes, but that is results from a low-carb diet over a short time-span (about 24 weeks or less)

The Bad News or Negative Research

There is research on the long-term effects of the low-carb diet. This is because a long-term ketogenic diet has been in use for the treatment of epilepsy.

Although the study is small, the results are VERY concerning.

One study, over a 6 year period following 129 participants, concludes:-

Elevated levels of blood triglycerides: High levels of fatty molecules in the blood. Can lead to atherosclerosis (furred arteries) and heart disease.
Heart arrhythmias
Osteoporosis
Hyperuricemia: high levels of uric acid in the blood. This can be linked with gout.
High cholesterol levels
Hepatitis
More susceptible to infectious diseases
Pancreatitis
Kidney damage and an increase in the risk for kidney stones
Anemia
Increase in the risk for cancer

The pros and cons are a bit contradictory Doc.

Yes, because the research about the benefits is based on short-term use of the low-carb diet.

Conclusions

As always, I am in favor of an all-round, sustainable, healthy eating plan.

Although, a low-carb or very-low-carb diet may not do any harm in the short term, evidence suggests that over longer periods it can cause health problems.

Furthermore, like all temporary diets, low carb diet weight loss tends to be temporary too. Indeed, some medical research suggests that dieting itself leads to weight gain.

I promote an all round healthy eating plan that includes all food groups in moderation. That is, plenty of fresh fruits and vegetables, lean meats, beans and pulses and healthy fats too.

Cut down on calories rather than carbs BUT do avoid processed refined carbs and white sugars.

For an idea of proven healthy eating plans, take a look at the Mediterranean and Dash diets

Thanks for reading and please check out some of our other posts.

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