Research Review What is the Best Diet for Weight Loss?

Why does dieting have to be so confusing?

Eat more of this, less of that. The fact is there are many ways to lose weight from changes to your diet, but which one is going to

get you results the fastest and keep the weight off long term? We have broken down the 4 most popular diets to help you decide,

which one might be best for you.

For the purpose of this review we have looked purely at the diets effectiveness on weight loss, both short and long term. Although

many of the diets have reported benefits outside of this, we have chosen not to explore these areas further.

Ketogenic Diet What Is It?

The Ketogenic Diet or Keto is similar to the Atkins Diet except it is an extreme version of a low carbohydrate diet - carbohydrate

intake is less than 20-50g a day. The premise of the diet is that by reducing your carbohydrate intake you force your body into a

ketosis state that means you use fat as a primary fuel source.

Does It Work?

A research review in 2014 compared the different diets from 48 randomised trials for overweight adults. The review found low fat

and low carbohydrate diets were the best for weight loss. The studies measured participants at 6 months, with low fat dieters losing

on average 7.99kg and low carbohydrate dieters losing 8.73kg. They followed up again at 12 months with low fat dieters losing on

average 7.27kg and low carbohydrate dieters’ 7.25kg. The conclusion was both showed significant weight loss and it came down to

what an individual feels they can adhere to. (Johnston et al., 2014).

What Are The Challenges?

High intensity or continuous exercise is very difficult on a Ketogenic diet. Research has found Keto Diets reduce exercise

performance in activities that are heavily dependent on anaerobic energy systems. These findings have clear performance

implications for athletes, especially for high-intensity, short duration activities and sports (Weiss et al., 2018). Other side effects can

be diarrhoea, headaches, fatigue and mood swings.

Intermittent Fasting What Is It? There are many different methods of intermittent fasting but all involve an eating pattern of fasting and feasting. The two most

popular being the 16-8 method where you eat for 8 hours of day and fast for 16 hours, and the 5-2 method where you have 2 days

of 500 calories and 5 days of 2000 calories.

Does It Work?

A 2017 study compared intermittent 5-2 fasting diet (25% of energy needs on fast days; 125% of energy needs on alternating "feast

days"), calorie restriction (75% of energy needs every day), and a no-intervention control. Mean weight loss was similar for

participants in the alternate-day fasting group and those in the daily calorie restriction group at month 6 with - 6.8% weight loss for

intermittent fasting and - 6.8% weight loss for calorie restriction. At 12 months the intermittent fasting group had - 6.0% weight loss

and calorie restriction had - 5.3% weight loss. Researchers concluded alternate-day fasting did not produce superior adherence,

weight loss, weight maintenance, or cardio protection as compared to daily calorie restriction (Trepanowski et al., 2017).

What Are The Challenges?

Intermittent Fasting has shown no short-term health impacts but more research is still needed on the long-term side effects (Harvie

and Howell, 2017). In saying this Intermittent Fasting isn’t safe for those with type 2 diabetes, children, pregnant or lactating

women, or anyone with a history of an eating disorder.

Paleo Diet What Is It?

The philosophy behind the Palaeolithic Diet or Paleo is that the human body has not adapted to civilization and rejects modern

ways of eating for foods that could have been hunted or gathered in the Paleolithic Era. People focus on whole foods – lean protein,

vegetables, fruits, nuts and seeds; while avoiding processed foods – sugar, dairy, legumes and grains.

Does It Work?

A 2014 study compared the Palaeolithic Diet to a low fat high fibre diet as per the Nordic Nutrition Recommendations (NNR). They

measured body fat mass in obese postmenopausal women via a DEXA scan at 6 months and 2 years. Both groups significantly

decreased total fat mass at 6 months with Paleo Diet - 6.5kg and NNR - 2.6 kg. After 2 years Paleo Diet was - 4.6kg and the NNR -

2.9 kg, concluding that the Paleo Diet had superior weight loss benefits at 6 months but no difference at 2 years. Both diets

coincidentally resulted in a decreased energy intake; 20% for Paleo and 12% NNR (Mellberg et al., 2014).

What are the Challenges?

Due to high protein intake there are concerns around red meat intake and cancer risk. In substitution analysis, replacing one

serving of red meat with other food sources of protein was associated with a maximum relative risk reduction of 62.4% (Lew et al.,

2016).

The Vegan Diet What Is It?

The vegan diet is a strict form of vegetarianism, excluding all animal products from your diet including dairy, honey and eggs.

People follow this diet for health and/or ethical reasons.

Does It Work?

A 2015 study compared vegan, vegetarian, pesco-vegetarian, semi-vegetarian and omnivorous diets. The study found that weight

loss at 6 months was greatest in the vegan group (-7.5% ± 4.5%), which was significantly different from the omnivorous (-3.1% ±

3.6%;), semi-vegetarian (-3.2% ± 3.8), and pesco-vegetarian (-3.2% ± 3.4%;) groups. Vegan diets may result in greater weight loss

than more modest recommendations (Turner-McGrievy et al., 2015). Interestingly all groups exhibited weight loss without

conscious calorie restriction.

What are the Challenges?

Cutting animal products from your diet can lead to nutrient deficiencies of B12, Vitamin D, calcium and iron to name a few. A 2014

study compared vegetarian diet, carnivorous diet rich in fruits and vegetables, carnivorous diet less rich in meat, and carnivorous

diet rich in meat. The results showed a vegetarian diet is related to a lower BMI but also showed that a vegetarian diet is associated

with poorer health - higher incidences of cancer, allergies, and mental health disorders (Burkert et al., 2014).

Our Approach Our approach at Better Being is to find a way of eating that is safe, effective and enjoyable for an individual. Based on the diets in

this review three universal keys can be derived when it comes to eating and weight loss:

1. Eat more vegetables – lots of colour. It keeps you healthy with vital nutrients like fibre and helps in satiety. Best sources of

fibrous fruits and vegetables – sweet potato, avocado and broccoli.

2. Have a good portion of protein with every meal – it keeps you full and helps in preventing muscle wastage. Manage your

consumption of red meat and focus on plant based or white meats such as chicken/fish.

3. Be conscious of what you eat – awareness leads to calorie restriction, which is why you lose weight.

The key is to find what works for your likes, your lifestyle and your body. Some clients will skip breakfast the days they don't train,

others will keep a food diary or some will have 3 meat free days a week. Having a coach, someone in your corner will help you in

finding the best strategy for you and hold you accountable in achieving your health and fitness goals.

To find a coach to help you on your weight loss journey head to www.betterbeing.com.au

Bibliography Ketogenic Diet Johnston, B., Kanters, S., Bandayrel, K., Wu, P., Naji, F., Siemieniuk, R., Ball, G., Busse, J., Thorlund, K., Guyatt, G., Jansen, J. and Mills, E. (2014). Comparison of Weight Loss Among Named Diet Programs in Overweight and Obese Adults. JAMA, [online] 312(9), p.923. Available at: https://www.ncbi.nlm.nih.gov/pubmed/25182101. Weiss, E., Wroble, K., Trott, M., Schweitzer, G., Rahman, R. and Kelly, P. (2018). Low-carbohydrate, Ketogenic Diet Impairs Anaerobic Exercise Performance. Journal of the Academy of Nutrition and Dietetics, [online] 118(9), p.A46. Available at: https://www.ncbi.nlm.nih.gov/pubmed/29619799 Intermittent Fasting Trepanowski, J., Kroeger, C., Barnosky, A., Klempel, M., Bhutani, S., Hoddy, K., Gabel, K., Freels, S., Rigdon, J., Rood, J., Ravussin, E. and Varady, K. (2017). Effect of Alternate-Day Fasting on Weight Loss, Weight Maintenance, and Cardio protection Among Metabolically Healthy Obese Adults. JAMA Internal Medicine, [online] 177(7), p.930. Available at: https://www.ncbi.nlm.nih.gov/pubmed/28459931. Harvie, M. and Howell, A. (2017). Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects—A Narrative Review of Human and Animal Evidence. Behavioral Sciences, [online] 7(4), p.4. Available at: https://www.ncbi.nlm.nih.gov/pubmed/28106818.

Paleo Diet Mellberg, C., Sandberg, S., Ryberg, M., Eriksson, M., Brage, S., Larsson, C., Olsson, T. and Lindahl, B. (2014). Long-term effects of a Palaeolithic-type diet in obese postmenopausal women: a 2-year randomized trial. European Journal of Clinical Nutrition, [online] 68(3), pp.350-357. Available at: https://www.ncbi.nlm.nih.gov/pubmed/24473459. Lew, Q., Jafar, T., Koh, H., Jin, A., Chow, K., Yuan, J. and Koh, W. (2016). Red Meat Intake and Risk of ESRD. Journal of the American Society of Nephrology, [online] 28(1), pp.304-312. Available at: https://www.ncbi.nlm.nih.gov/pubmed/27416946. Vegan Diet Turner-McGrievy, G., Davidson, C., Wingard, E., Wilcox, S. and Frongillo, E. (2015). Comparative effectiveness of plant-based diets for weight loss: A randomized controlled trial of five different diets. Nutrition, [online] 31(2), pp.350-358. Available at: https://www.ncbi.nlm.nih.gov/pubmed/25592014. Burkert, N., Muckenhuber, J., Großschädl, F., Rásky, É. and Freidl, W. (2014). Nutrition and Health – The Association between Eating Behavior and Various Health Parameters: A Matched Sample Study. PLoS ONE, 9(2), p.e88278.