Food we eat, to a larger extent, is an integral part of our lives. What we eat, we become; as long as we eat healthy food, we stay fit. However, in real life we sometimes get distracted. Saying no to tasty food is no easy task, no matter how unhealthy it can be.
Therefore, eating healthy foods should become a habit, a way of life. People nowadays try different eating patterns with the intention of staying healthy and keeping diseases at bay. One such method which has gained immense popularity across the globe is the “ketogenic diet” or most commonly known as the “keto diet”.
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What exactly is a “Keto Diet”?
Although the keto diet has recently taken the world by storm, it is not entirely a novel concept. It has been used in treating intractable epileptic patients for many years. In 1970, an American physician called, Robert C. Atkins developed a low-carbohydrate diet mainly as a mean of losing extra weight. After going through many scientific researches, it later gained its place as a treatment option for drug-resistant epilepsy.
A ketogenic diet is simply a high-fat, low-carbohydrate diet with adequate protein and calories in it. There are several types of ketogenic diets. The traditional keto diet contains a 4:1 formulation of fat content to carbohydrate along with protein.
On the other hand, a classic 4:1 keto diet contains 90% fat, 8% protein and only 2% carbohydrate in it. Now there are many alternative types of keto diet as well. They have slight improvements in them, mainly to increase compliance and their nutritional value.
The main purpose of a keto diet is to mimic the state of fasting. Scientists were able to identify ketone bodies in the blood after a period of fasting. They wanted to obtain the benefits of fasting by introducing ketone bodies by some other mean.
Usually, it is glucose, the end-product of carbohydrate metabolism that acts as the main substrate for energy production in the body. However, when glucose is no longer available, the human body makes use of alternative sources for generating energy such as ketone bodies, which are compounds produced by metabolizing fatty acids. The shift from glucose to ketones and fatty acids as the main source of energy usually takes up to about one week.
Ketones are organic compounds that are produced mainly by mitochondria in liver cells. To a lesser extent the heart, intestines, and the brain also produce ketone bodies.
There are mainly three types of ketone bodies. They include acetoacetate, b-hydroxybutyrate and acetone. Of them acetoacetate and b-hydroxybutyrate are important as sources of energy.
They actually produce more energy than glucose. Therefore, they are considered to be more metabolically efficient than glucose.
The keto diet is so popular and widely available that we hear of a number of positive things about it every day. However, is there really any valid scientific basis behind these so-called health benefits?
Is it really worth all the hype? Does keto diet truly provide all those health benefits as its users proudly claim? This is an attempt to uncover the scientific reasons behind these claims. Let’s dive in and find out.
1. Decrease Appetite
Hunger is the main obstacle for continuing any type of diet. Usually, a lot of determination and commitment should be there to overcome the will to eat constantly or to stop eating after consuming the right amount. This is almost always something easier said than done.
However, studies show that short term, high-protein, low-carbohydrate ketogenic diets are capable of reducing hunger. As a result, they lower food intake more significantly compared to high-protein, medium-carbohydrate nonketogenic diets.(1)
It is easier to follow a diet for a longer period when your appetite is under control and you no longer crave those unhealthy snacks. This also provides an extra benefit as you will be cutting down your unwanted calorie intake without taking much effort on your part.
2. For Weight loss
The main target of adhering to some kind of diet plan or another is to lose some extra weight. If not for that, no one would go through all those pains of avoiding the favorite food items on the planet, right?
Luckily, enough there’s sufficient scientific evidence to show that a ketogenic diet is indeed capable of reducing weight efficiently over a reasonable period of time.
One systematic analysis reveals that a low-carb keto diet shows a significant benefit over a low-fat diet in reducing body weight within a short duration of time.(2) They were able to observe about 4kg weight loss at the end of 6 months. In addition, at least 1kg loss in weight was evident at the end of one year.
Furthermore, it reveals that this short-term weight loss comes with another bonus advantage. That is; it mainly attributes to losing abdominal fat, one of the most difficult goals as far as weight loss is concerned. This is a huge benefit for many obese individuals with increased risk of cardiovascular disease.
What’s more interesting about a keto diet is that it induces a very rapid weight loss. Although it is not entirely clear how, scientists believe this loss is partly due to the water loss due to ketosis. Or else it could also be due to restricted calorie consumption in the meal as a whole. Afterall, a keto diet is known for inducing early satiety, allowing the consumer to be content with a lesser amount of food than before.(3)
A ketogenic diet maintains these weight loss benefits over a long duration of time. A recent study reveals that a ketogenic diet is effective even up to one to two years. Besides, it reduces the degree of deposition of fat in and around internal organs of the body. (reduce fat deposition in visceral adipose tissues). This ultimately leads to reduced risk of obesity and the overall disease burden.(4)
3. For treating multiple neurological diseases
Ketogenic diet has always had a prominent place among treatment modalities for neurological diseases for several years. Scientists are now paying more attention towards identifying new ways in which they can implement keto-therapeutics for neurological disorders in practice.
· Epilepsy
One of the earliest uses of a ketogenic diet was to use in the treatment of intractable epilepsy. There are many theories trying to explain how a low-carbohydrate diet can reduce seizure occurrence or its frequency.
One theory suggests that when ketone bodies become the main substrate for producing energy instead of glucose inside the brain, it lowers the rate of seizure generation.
Glucose is a rapid source of energy. When a person is on a keto diet, his or her blood glucose level lowers and the body adapts to using ketone bodies instead, which in fact is rather an anerobic state of producing energy.
In an anerobic state, the energy availability is quite low compared to that of an aerobic state. Therefore, neurons no longer have extra energy to fire at an abnormal rate. As a result, the seizure activity gradually reduces.(5)
According to another theory; a ketogenic diet is capable of inducing synaptic stability in neurons. A neuronal synapse is a kind of a gate-way between two neurons and it relays messages from one neuron to another using special chemical compounds called neurotransmitters.
In a seizure, these synapses get unstable or over-excited; triggering at an abnormal frequency. This theory suggests that a keto diet increases GABA levels in the body, which is the main inhibitory neurotransmitter available. Finally, this leads to reduction in seizure activity.
· Alzheimer’s disease
Alzheimer’s disease is a progressive type of dementia in which cognitive deterioration occurs over a period of time. Unfortunately, there is no definite cure for Alzheimer’s disease (AD) just yet and only medications that delay the disease progression exist.
However, scientists are now experimenting with ways to utilize ketogenic diets in the treatment process of a chronic, deteriorating neurological disease like AD.
Several studies indicate that the dietary patterns of these patients have the potential of either increasing or decreasing the rate of AD progression. Diets rich in polyunsaturated fatty acids and monounsaturated fatty acids are capable of delaying the onset of AD.(6)
Patients on keto diets for both short and long durations of time, have shown improved results in the Alzheimer’s Disease Assessment Scale for cognition. In addition, when used for a comparatively longer duration, memory has improved significantly as well.(7)
4. Lowers Blood Sugar level
Several studies indicate that keto diet has a very positive impact on glycemic control in patients with Type-2 diabetes.
In one study in which individuals with Type-2 diabetes consumed a keto diet for a period of 24 weeks; they were able to observe significant improvement in glycemic control. They observed a significant decrease in HbA1c values, an indicator of long-term glycemic control.
Besides, they were also able to reduce the doses or completely eliminate the diabetic medications at the end of the trial. This achievement was quite remarkable in individuals taking insulin, as participants who were already on about 40 to 90 units of insulin before the study, were finally capable of eliminating their insulin usage at the end, while achieving good glycemic control during the process. (8)
5. Lowers High Blood Pressure
According to some studies, there’s a trend towards a decrease in both systolic and diastolic blood pressures after consuming a ketogenic diet for about 6-12 months. Most studies mainly reveal a decrease in the diastolic blood pressure.(9)(10)
High blood pressure or hypertension has a close connection with high salt intake and obesity. Dietary modifications are paramount in controlling high blood pressure in patients. However, there is scientific data showing that in a setting of a healthy diet, when either protein or monounsaturated fat partially substitute the carbohydrate component, it can actually lead to a reduction in blood pressure, more than what can be achieved via salt restriction.(11)
6. For treating Mood Disorders
Although several pharmacological and non-pharmacological treatment modalities are available for mood disorders; it still remains a serious mental health issue across the globe.
Studies reveal that the neurological effects of ketogenic diets usually happen around the same aspects responsible for causing mood disorders. As a result, scientists are exploring ways to utilize keto diets in the treatment process of intractable mood disorders.
Increased GABA transmission monoamine transport, and reduced glutamate transport are some of the effects of a keto diet favoring treatment of mood disorders.(12)
7. As a treatment modality for cancer
There is still plenty of room for improvements in our tactics we use for fighting cancer. Despite all the efforts, a definite cure for cancer is not yet in sight. As a new approach for fighting cancer, scientists are considering making use of keto diets.
In cancer, metabolic alterations happen inside tumor cells. Increased glycolysis and diminished tricarboxylic acid (TCA) cycle activity are some examples for such changes. Scientists try to use keto diet to target these metabolic changes and affect glucose metabolism in the cancer cells.
Cancer cells have dysfunctional mitochondria inside them. Mitochondria are the powerhouse of a cell. It mainly metabolizes glucose to produce energy. When using a ketogenic diet; the main energy substrate becomes ketones instead of glucose.
Since, mitochondria in cancer cells are not functioning properly, they find it difficult to adapt to using ketones as the main energy source. As a result, a lesser amount of energy is produced depriving cancer cells of energy they require to grow as a tumor.
Furthermore, studies reveal that ketogenic diets can affect amino acid metabolism, formation of blood vessels, signaling pathways and gene expression of the tumor cells restricting their growth and spread.(13) Therefore, keto diet plays a very prominent role as a new therapeutic option with a lot of potential among many other treatment modalities available.
8. For treating Polycystic Ovarian Syndrome
Polycystic ovarian syndrome (PCOS) is an endocrine disorder in which women develop period irregularities, infertility, obesity and features of hyperandrogenism like hirsutism (extra hair growth) and acne. They can also develop insulin resistance, type-2 diabetes mellitus and hyperinsulinemia.
In a study where participants adhered to a strict keto diet consisting of less than 20 g of CHO per day, for a period of 24 weeks showed a significant decrease in fasting serum insulin and free testosterone.(14)
Another study shows that after adhering to a keto diet, glycemic control, fasting insulin level, testosterone level, and insulin sensitivity gets improved.(15)
9. Friend of gut microbiota
Whether, a ketogenic diet is truly a friend or foe of the gut microbiome still remains a bit controversial. If there’s a single thing that almost all scientific research done on the subject agree upon; it’s that a keto diet possesses the ability to alter the composition of microorganism populations living in our guts. The real-life implication of this scientific discovery remains a bit divisive though.
There are scientific studies revealing both positive and negative effects. However, it is safe to say that studies ending up on a positive note are higher compared to those revealing a negative impact.
In a recent study, where two groups of healthy and epileptic infants participated, after giving ketogenic treatment for at least one week to the epileptic group, they have identified that the gut microbiome pattern in epileptic infants differed significantly from the healthy group. (16)
Furthermore, their findings reveal that keto diet has the ability to alter the composition of microorganisms in the gut from that of pathogenic microbes to more beneficial ones.
Studies reveal that a healthy population of gut microorganisms gives many beneficial outcomes related to the nervous system such as reducing seizure frequencies and involvement in the blood-brain barrier and glial cell development.(16)(17)
However, there is evidence showing that a keto diet has the potential of reducing prebiotics and probiotics in the gut as well.(17) Probiotics are basically a type of “good” bacteria that the digestive system needs, while prebiotics are the foods those probiotic bacteria need to survive. Therefore, it might be necessary to consume such components additionally in order to maintain the end-quality of the ketogenic diet.
Here are few scientifically proven tips to maintain gut health while taking a ketogenic diet;
- Consume more plant proteins
- Reduce protein intake from animal sources
- Include fermented food items like yoghurt in your diet
- Avoid artificial sweeteners
- Avoid processed food items as much as possible
- Consume unsaturated fatty foods in right quality and quantity
- Implement prebiotics and probiotics in your meals
Luckily enough, we have sufficient substantial scientific evidence to support the positive effects of a ketogenic diet as far as weight maintenance and benefits against certain disease conditions are considered.
However, the keto diet has its own shortcomings, mainly depending on individual health conditions.
Although, most of its side effects are not showing very serious implications in a majority of consumers, further scientific research has to be conducted to be certain of their long-term impact.
Until then, it is better for people with other co-morbidities like diabetes mellitus and heart disease to seek medical advice prior to making any major dietary change.
References
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