The Good, Bad and Ugly of Nutrition

With several weight loss diets available it can be difficult to know whether they are worth trying or even beneficial for your health. Some diets focus on reducing the amount you eat, whereas others emphasise on restricting the amount of calories or certain nutrients such as fats and carbohydrates you consume. Unfortunately no single weight loss diet will be suitable for everyone due to a number of reasons; however we have reviewed some of the current popular weight loss diets and the facts behind them;

The Paleo Diet

This diet is based on the concept that modern humans ought to be eating as our hunter gatherer ancestors ate. The theory behind the Paleo diet is that most modern-day diseases and health issues are related to the western diet and how we consume dairy, grains and processed foods. Therefore it empathises eating whole foods, lean protein, fruits and vegetables and nuts and seeds. Individuals should avoid processed foods, sugars, dairy and grains.

Numerous studies have found that following the Paleo diet can cause a significant amount of weight loss and a reduction in waist size, as dieters eat less carbs and proteins and consume fewer calories (1, 2, 3). Dieters also have a reduced risk of heart diseases (4, 5) however as the diet cuts out whole grains, legumes and dairy foods it ends up eliminating numerous nutritious and healthy foods.

The Atkins Diet

This is currently the most popular low-carb weight loss diet. It claims that you can lose weight despite eating as much protein and fat as you like, followers are only advised to avoid carbs as this can reduce your appetite. The diet has four phases, the first of which you are advised to eat under twenty carbs per day and the remaining phases ask dieters to slowly reintroduce healthy carbs back into the diet as the goal weight approaches.

Studies have found the Atkins diet can lead to faster weight loss (6, 7). Low carb diets such as the Atkins diet have also been found to reduce belly fat (8, 9, 10) as well as reducing the risk factors for diseases such as cholesterol, blood sugar and blood pressure (11, 12, 13).

The Ultra-Low-Fat Diet

The ultra-low-fat diet restricts the amount of fat that can be consumed to fewer than ten percent of consumed calories. Dieters will usually only consume plant based food and has a very limited intake of meat. ‘The diet has been shown to be successful for weight loss in obese individuals (14), however is not suitable as a long term diet.

Benefits of this diet include a significant improvement in type two diabetics (15, 16) and an improvement in risk factors for heart diseases (17, 18). Unsurprisingly though the ultra-low-fat diet can create long term problems as fat plays an important role in the body such as building cell membranes and hormones. Due to the limited intake and variety of foods, this diet is very hard to follow for a long period of time.

Intermittent Fasting

This is more of an eating pattern that you follow in cycles between periods where you fast and eat. This diet does not restrict food, it just states when food should be eaten in order to restrict calories. Some of the most popular ways of intermittent fasting include;

– The 16/8 method – skipping breakfast and restricting eating to eight hours a day only

– The 5:2 diet – restricting intake of calories to 500-600 twice a week and eating like normal on the other five days of the week

– The warrior diet – eating a small amount of raw fruits or vegetables in the daytime and one main large meal at night

Intermittent fasting appears to be generally very successful (19) and causes less muscle loss than the standard calorie restriction diets. Dieters also experience a short term increase in metabolic rate (20) and a reduction in markers of inflammation, cholesterol levels and blood sugar levels (21, 22, 23).

To successfully lose weight and keep it off, a combination of healthy eating and exercise is always recommended. Remember when choosing a new diet routine for yourself, you should always look for one that you can foresee yourself sticking to in the future and always speak to your doctor before beginning a new diet plan.

To learn more about the good, the bad and the ugly of diets and nutrition, see our nutrition diplomas page.

[Sources]

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2. Osterdahl, M., Kocturk, T., Koochek, A. and Wandell, P.E., 2008. Effects of a short-term intervention with a paleolithic diet in healthy volunteers. European journal of clinical nutrition, 62(5), pp.682-686.
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