By now, pretty much everyone has at least a vague understanding of the fact that reducing carbohydrate intake considerably is one of the most effective weight loss tricks one can implement in the diet . Digging deeper than that, however, often yields more questions than answers.
For instance, there is a low carb approach, and then there are so-called ketogenic diets – and those, although have some general points in common, are only extended family to each other…at the very most it seems.
It may appear to someone fairly new to those concepts that transition to the ketogenic heaven is only two slices of toast apart from a traditional low-carb diet.
The reality, however, is more complicated – although both diets are definitely low carb, especially compared to the dreaded “Western diet” (yes, the one with tonnes of processed unhealthy foods), the similarities pretty much stop right there. In fact, low-carb and ketogenic approaches are structured differently and focus on different aspects of nutrition and metabolism.
Sounds confusing? Don’t worry – we’re here for you. Today, we’ll discuss both approaches in detail and highlight some important points, helping you make well-informed choices and implement an effective weight loss strategy that is 100% right for you!
Low Carb Diets 101
Definitions first, and low-carbohydrate diet pretty much describes itself in its name. Unfortunately, the term does not provide enough clarity – after all, “low” is relative, meaning we need to compare it to something supposedly “normal” and/or “high”. Although there is no uniform definition, according to the Mayo Clinic , “a daily limit of 60 to 130 grams of carbohydrates is typical with a low-carb diet.
These amounts of carbohydrates provide 240 to 520 calories”, which is well under 30% even for the stricter side of average daily requirements.
In contrast, the Dietary Guidelines suggest that 45-65% of total daily calorie intake comes from carbs , meaning that an average person would need to consume 225-325 grams of carbs daily . In other words, low carb diets limit carbohydrate intake considerably, typically cutting out at least 50% of usual intake.
So how does the low carb approach work?
If you cut out the carbs without replacing calories, you’ll likely start losing weight pretty quickly. However, replacing the “missing” calories with fat or protein will likely result in a plateau. In other words, sometimes calorie restrictions in general, not eliminating carbs as such, cause weight loss.
In saying that, low carb diets do have a number of distinct, remarkable advantages. For instance, low carb approach helps reduce insulin levels , boost metabolism , regulate cholesterol levels  and reduce or even reverse risk factors for cardiovascular disease .
On the flip side, the low carb approach may lead to dangerous yo-yo dieting behaviours, especially when implemented without sufficient knowledge and planning . It does not mean that low carb diets must be discouraged entirely, however – consulting a professional such as a dietitian or a skilled personal trainer basically eliminates such risks.
Ketogenic Diets 101
Unlike low carb approach, ketogenic diets go far beyond restricting a single macronutrient. Instead, a ketogenic diet requires very specific changes to all three macronutrients: carbs, fats and protein .
A ketogenic diet is not only low carb (very low carb, in fact) but also high-fat and moderate in terms of protein. The golden ratio is getting 75% of energy from fats, 20% from protein and 5% from carbs . As the name suggests, such strict regulations pursue a purpose of putting you in a state of so-called nutritional ketosis .
Although this approach may seem a bit too strict at a glance, ketogenic diets (often referred to as keto) have some solid scientifically proven health benefits. For instance, a recent review indicates that over 20 high-quality studies have clearly demonstrated that keto is the way to go for weight loss . Similar to general low carb diets, ketogenic plans can improve insulin sensitivity  and help prevent and manage heart disease .
Not too sure what we mean by ‘ketosis’? Scroll down to the next section to find out.
The Difference Is In The Ketones
Tiny molecules derived from fat produced in the liver , ketones are accountable for the difference between low carb and ketogenic diets. Anytime you restrict the consumption of carbohydrates, your body opts for burning fat for energy. For instance, it turns fat into – you guessed it – ketones, which then supply necessary energy for the hard-working brain .
In other words, when your body’s glucose storages are exhausted, ketone production increases.
To put things into perspective, let’s look at some numbers. If we measure blood levels of ketones in someone who maintains a traditional high-carb diet, it’s likely to be somewhere in between 0.1 and 0.2 millimoles (mmols) .
Interestingly, a moderate-to-low-carb diet has no significant effect on this . However, if you follow the ketogenic pathway religiously, blood ketones rise to 0.5 -5.0 millimoles, putting you in a state of “nutritional ketosis” .
How To Control The Macros For Both Diets
Let’s have a look at the implications of both approaches for macros control.
We’ve already established that low carb diets suggest consumption of ~50-125 grams of carbohydrates daily . This is quite a broad range – and ketogenic diets are much stricter. It appears that in order to trigger nutritional ketosis, prompting your body to begin relying on fat as primary fuel, one needs to keep carbs below 50 grams daily, consistently .
In a similar fashion, eating too much protein can easily kick you out of keto. This is because protein can be broken down to glucose during a process called gluconeogenesis . By consuming over 20-25% of daily calories from protein, you are putting yourself at risk . Of course, there is no need to be so precise on a general low carb diet, where it’s just advisable to maintain moderate-to-high protein intake combined with carb and calorie restrictions .
Finally, fats are the focus of ketogenic diets. As outlined above, as much as 70-75% of daily calories must come from high-quality fats in this instance, as fats become a primary fuel. In fact, when there are no carbs available, our body starts using fat as a readily available fuel source .
The calculations may seem a bit overwhelming initially. but given that ketogenic diets get more and more support from researchers, this approach is definitely worth your attention.
Which Diet Is Best For You?
As you’ve probably guessed, there is no uniform answer to this question. Ultimately, both approaches are effective as far as weight loss goes, provided you are sticking to a plan created for your individual needs by an experienced professional, such as your personal trainer or a skilled nutritionist. Both concepts are supported by research – and both are also criticised in numerous studies.
Otherwise, it all comes to your individual preferences. Of course, low carb approach is a bit less drastic when it comes to your current lifestyle. Besides, some people just can’t seem to get used to ketogenic dieting – and we can’t blame them, especially when it comes to the first few weeks, when adverse effects are especially tough. On the other side, ketosis is likely to yield faster results, and many professionals swear by it .
The best way to decide is to try both approaches and see what works better for you! And lastly, don’t forget to get support from your personal trainer to ensure your progress stays on track while you’re dieting. Hard work and dedication pays off – by getting through the temporary discomfort of nutritional adjustments, you are making a huge leap towards the healthiest, happiest version of yourself ever!
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