In this simple article, Shane Nugent, our resident Nutritionist, explores multiple popular diet types and provides us with a simple overview of each one...
There are SO many diets out there, they’re all designed to reduce your calorie intakes and therefore create a calorie deficit, but whichever approach you personally choose to follow is entirely up to you.
Very Low Energy Diets, and Low Energy Diets
Very low energy diet = 400-800 Cals per day. Low energy diet = 800-1200 Cals per day. Generally involve pre-made products eliminating the need for cooking.
PROS – Rapid weight loss can occur (1-2.5kg per week)
LIMITATIONS – Do not necessarily outperform Low energy diets, nor do they generally have long-term benefits.
Low Fat Diets
Low fat diets generally contain 25-30% fat. Very low fat diets generally contain 10-20% fat.
PROS - These types of diets are well supported by international health bodies due to large areas of research containing health benefits associated with this approach. Macronutrient ranges are pretty flexible. Doesn’t pose carbohydrate-type foods in a negative light.
LIMITATIONS - Suggests that FAT is the cause of weight gain, and therefore limiting fat intake will result in weight loss, when total calories are actually the overriding factor. Very low fat approaches have little evidence to suggest their success, and can easily challenge long term adherence.
Low Carbohydrate Diets
50-150g of Carbs per day, OR, up to 40% of intakes formed from Carbs per day.
PROS - This approach generally automatically leads to an increase in protein intakes. There is a large amount of flexibility in other macronutrient proportions, and food choices too. Does not vilify foods based on fat contents.
LIMITATIONS - Again, limiting any macronutrient can falsely convey the message that a single macronutrient is responsible for weight gain, when in fact the total cals is the most important factor.
Diets generally contain a max of 50g of carbs per day, or a maximum of 10% of total calorie intakes from carbs.
PROS - Automatically facilitates the creation of higher protein intakes. Suppresses appetite and controls levels of hunger. Generally involuntarily results in a caloric deficit, even if you aren’t trying to create this environment. Simplifies dietary planning as well as the decision-making process.
LIMITATIONS - Ketogenic diets minimise/eliminate carbohydrates which can have negative effects on various health markers and can even restrict disease prevention. Can compromise energy output during training sessions. Can challenge long-term sustainability. Despite its popularity it doesn’t appear to have any additional benefits over other dietary strategies.
High Protein Diets
High protein diets include 25% or more calories sourced from protein, OR, a total of 1.2 to 1.6 g of protein per KG body mass consumed each day or more...
‘Super high protein’ diets contain more than 3g protein per KG of body mass consumed daily.
PROS - High protein diets have a large body of evidence supporting improvements in body composition in comparison to current government minimum recommendations (0.8g Protein per KG body mass per day)
LIMITATIONS - May be tricky to uphold on a day to day basis, sourcing this level of protein on a daily basis can have practical issues and may have limitations financially speaking. Higher intakes of protein, especially very high level intakes can displace calories from other macronutrients (carbs and fat) and omit the benefits that increases in these macronutrients would display, such as compromises to energy levels during performance and training.
There are many different types of intermittent fasting, but for the purpose of this review they will be split into the following 3 sections:
‘Alternate Day Fasting’ = alternating 24hr Feeds, and 24 hr fast periods.
‘Whole Day Fasting’ = 1-2 complete days of fasting per week
‘Time Restricted Feeding’ = Restricted periods for feeding, such as 16-20hr fast, and 4-8 hr feed daily.
PROS - All intermittent fasting methods show fair evidence for its effectiveness. The first 2x methods don’t involve tracking of macro/micronutrients. Time restricted feeding has a growing body of evidence to suggest fat loss can be achieved whilst still maintaining strength.
LIMITATIONS - It is still unclear if intermittent fasting approaches can outperform standard daily calorie deficit approaches, It’s also likely that although there has been viable evidence to suggest these methods as relatively sustainable weight loss methods, a more evenly distributed approach to macronutrient consumption throughout the day could give even further body composition benefits.
As you can see there is a WHOLE WORLD of diets out there, these are just the major diet types, but the vast majority of popular diets will fall within these categories.
There can also be grey areas and crossovers between the diet types too but hopefully this blog gives you a much better basic understanding of the variety of diet types out there, what they entail, and their benefits and limitations.