5 Fad Diets: A Dietitian Lays Down The Facts

By Sally Shi-po POON (Registered Dietitian)

It’s summertime again! Many people would like to shed a few pounds and get tempted by a range of ‘quick fix’ diets offering the promise of rapid weight loss. Sadly, there is no magic solution for sustainable weight loss. Our dietitian Sally Shi-Po Poon reviews the top 5 fad diets as follows:

1. Ketogenic diet

The ketogenic diet is a low-carbohydrate, high-fat eating plan that has been used to control seizures in some people with epilepsy. The diet excludes carbohydrate foods such as grains, dairy, legumes, most fruits and starchy vegetables.

Supporters claim ketogenic diet can help burn fat and lose weight efficiently but evidence on its long-term effects is lacking currently. It may be challenging to follow this diet as it can cause side effects such as brain fog, fatigue, irritability, headaches, and constipation.

2. Gluten-free diet

A gluten-free diet eliminates all foods containing gluten. Gluten is found in wheat, barley, rye, malt, and cross-contaminated oats. You may lose weight when cutting out energy-dense gluten-containing products such as cakes, cookies, batter-fried foods, and beer.

However, gluten-free does not necessarily mean low-calorie because some gluten-free products actually contain more sugar and fat than their gluten counterparts.

3. Intermittent Fasting

Intermittent fasting involves short periods of fasting with either no food or very small amounts of food, and periods of unrestricted eating. A very popular intermittent fasting regime is called the “5:2 diet” – two days a week you eat less than 500 to 600 kcal, the remaining five days you eat as usual. People can achieve some weight loss if they don’t overeat on “feed” days.

However, fasting can make you feel dizzy, irritable, and tired, make it difficult to concentrate at work, and lack of energy to carry out physical activity. It is definitely not suitable for people with diabetes due to the risk of hypoglycemia (low blood sugar level).

4. Raw Vegan diet

Raw vegan diet has been claimed for weight loss as well as disease prevention. From the nutrition point of view, it can be healthy if you have a nutritionally balanced vegan diet with the necessary supplements like vitamin B12, however, it is not a guarantee of weight loss as vegan foods often contain similar amounts of calories as non-vegan foods.

While some foods are good to have raw, others are more nutritious cooked – like tomatoes and asparagus – as the availability of lycopene and lutein are found to be higher. Some foods cannot be eaten raw at all such as potatoes, legumes and lentils. In addition, raw foods are not suitable for children, pregnant women, elderly people and cancer patients with weakened immunity.

5. Juice Cleanse

Juice cleanse involves consuming vegetable and fruit juice for a short period of time, typically one to five days. Supporters claim it can detox our body, boost immunity, and shed some pounds quickly. However, evidence to support its recommendation is lacking. Basically, our liver and kidneys can remove waste from our body every day.

It is not recommended to do juice cleanse too often or for a long period of time because some key nutrients are lacking, for examples: protein, iron, omega-3 fatty acids, zinc, and calcium. Potential side effects include fatigue, dizziness, nausea, and headaches. Inadequate protein intake can make you lose muscle mass and affect the metabolic rate. Once you resume normal eating, your weight can rebound easily.

When a diet plan sounds too good to be true, it probably is. Always seek a qualified nutritionist or dietitian for proper advice – make small changes in eating habits and lifestyle that you will be able to sustain in the long term is key to success!

Sally’s Nutrition Blog @ Hong Kong Tatler: https://hk.asiatatler.com/life/ask-the-expert-diet-trends-in-2018