It appears that within the health and fitness industry, the popularity of ‘low-fat diets’ has well and truly declined into nothingness.
This has been replaced by the now common suggestion that carbohydrates (highly processed carbohydrates in particular) are to blame for the rapid weight gain (and health implications of that weight gain) of the population.
This, in turn, has seen the rising popularity of diets that somewhat demonise carbohydrates.
These diets (for example, ‘The Paleo Diet’ and ‘The Atkins Diet’) are typified by a total exclusion of processed carbohydrates, and often involve the severe restriction on non-processed carbohydrates as well.
As a result of these restrictions, these diets often recommend a relatively high intake of fat, with a high or moderate intake of protein.
Arguably the most popular (and at times controversial) of these diets, is The Ketogenic Diet.
The Ketogenic Diet is a way of eating typified by an extremely low carbohydrate intake and a relatively high fat intake, with a moderate protein intake.
So what makes the Ketogenic Diet different from other low carbohydrate, high fat diets?
Now, when I say extremely low carbohydrate intake I truly mean an EXTREMELY low carbohydrate intake.
While undertaking the Ketogenic diet, it is not uncommon to for 20 grams of carbohydrates to be the upper limit of carbohydrates consumption PER DAY.
Now, to try and put that into perspective, a medium sized banana will contain 20 grams of carbohydrates.
So why keep carbohydrate intake so low?
The Ketogenic Diet and Ketosis
The reason that carbohydrate intake is kept so low during the Ketogenic Diet is to promote a state of ketosis in the body.
Now, while Ketosis sounds like a bit of a fancy buzzword, it is important to note that ketosis is a normal occurring metabolic process that happens within the human body.
You see, the human body has the capacity to use both carbohydrates and fats for energy.
In fact, these two macronutrients are our key sources of energy.
It is often suggested that fats are used for energy when the body is at rest, while carbohydrates are used for energy during exercise.
This is not quite the case.
At any given time we are breaking down both fats and carbohydrates for energy.
The percentage of energy coming from each substrate changes accordingly in response to changes in time of day, exercise intensity, and other variable, but at any one time we are getting energy from both.
Interestingly, when there are insufficient carbohydrates available to meet the energy demands of the body, the rate of fat metabolism will increase as an alternative way to meet those energy requirements.
This increased rate of fat metabolism is suggested to promote fat loss, while also improving various different markers of health.
A secondary product that is produced as a result of this increase in fat metabolism are Ketones.
Ketones are an acid that can also be used for energy.
So Ketosis describes a state of the body where fat stores are broken down and used energy at a rapid enough rate to produce significant amounts of Ketones as a by product.
The main goal of the ketogenic diet is to get the body into a permanent state of Ketosis.
This can only be accomplished by starving the body of carbohydrates, forcing it to use fats (and subsequently, Ketones) as its predominant sources of energy .
Suggested Benefits of Ketosis and the Ketogenic Diet
So what are the benefits of the Ketogenic Diet?
And what are the positives associated with being in Ketosis?
The first reason, and arguably the reason why The Ketogenic Diet is rising in popularity so rapidly, is that when the body is in a state of Ketosis, its ability to use fat for energy is improved considerably.
As carbohydrates are not readily available for energy, the body is therefore forced to breakdown fats to maintain normal function, and provide energy for daily activities, and any additional exercise.
This is suggested to create somewhat of a ‘fat-burning’ environment, where fats are readily used for energy.
This increase in fat metabolism can lead to significant increases in fat loss .
The second reason that the Ketogenic Diet has become increasingly popular is due to its effect on various markers of health.
The reduce carbohydrate intake and increase fat metabolism associated with the Ketogenic diet has been linked to reduced risk of diabetes, improved reduced resting blood sugar levels, resting blood pressure and, reduced blood cholesterol levels .
Negatives of the Ketogenic Diet
Now, unfortunately, if something sounds too good to be true, it often is.
While thereis a number of benefits associated with the Ketogenic Diet, there a few negatives as well.
Firstly, we often experience a number of withdrawal like symptoms when we completely remove carbohydrates from our diet.
These symptoms often last one or two weeks, but can extend beyond that.
These symptoms can include mental and physical fatigue and lethargy, headaches, muscle and stomach cramps, excessive sleepiness, and bowel irritability.
Additionally, if you are an individual who likes to train in the gym regularly, or plays sport at a high intensity, you may experience a loss of performance .
This is due to the reduction in carbohydrates available for energy.
Carbohydrates are the body’s first choice for energy during high intensity activity, as it is easy to breakdown, providing a rapid source of energy.
Fats take more time to breakdown, providing a slower energy production cycle.
This can reduce physical performance, due to a reduction in energy production.
What the Ketogenic Diet Looks Like
So, noy you have a basic understanding of what the ketogenic diet is, and the positives and negatives associated.
But what does the Ketogenic Diet really involve?
As mentioned earlier, the basic principles of the Ketogenic Diet are easy to understand.
Eat lots of fats, don’t eat carbs.
But it isn’t quite that simple.
Looking at the Ketogenic Diet in greater detail, we start with macronutrient breakdown.
A typical breakdown of macronutrients for the Ketogenic Diet is a massive 70% of your daily energy intake energy coming from fats, 25% coming from protein, with the remaining 5% coming from carbohydrates.
This means that each daily meal should have a reasonable serve of protein and a large serving of fats.
There are also some foods that should be completely avoided.
These are quite obvious, and should be avoided due to the high amount of carbohydrates they contain.
These foods include anything with high sugar content such as candy and sweets, soda, and ANY fast foods.
They also include anything that is made-up of mostly carbohydrates such as breads, cereals, grains beans and most legumes, any starchy vegetables (such as potatoes and sweet potatoes.), fruits, and most sauces and condiments.
This also includes anything that is advertised as ‘low fat’ (with a special mention to low fat dairy).
So, by making sure that you eat foods containing only fast and proteins, and avoiding any of those carbohydrate dense foods, you can start undertaking the Ketogenic Diet immediately.
The Ketogenic diet is a way of eating that is typified by an extremely low carbohydrate intake in conjunction with a high fat intake.
The main goal of the Ketogenic Diet is to promote a state of Ketosis in the body.
Ketosis has shown to promote fat loss, leading to reductions in body weight, and have positive effects on various markers of health.
There are withdrawal like symptoms associated with the Ketogenic Diet that can result in feelings of illness and a significant lack in physical performance.
So if weight loss is your main goal, the Ketogenic Diet may be a fantastic solution.
Although, if you play sport at a high level, or enjoy training at a high intensity regularly, it may not be the best option for you.
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