The Dangers of Meal Replacement Diets

Spring and Summer are often times at which we feel pressured to slim down in order to look good in a bikini or to feel confident in our Summer clothes, so it’s not surprising that many people choose meal replacement diets to lose weight quickly or to kick-start their diets. However these meal replacement products can be dangerous and actually do our bodies more harm than good, despite the vast amount of health benefits or rapid weight loss that they claim to provide.

For me personally I find it bizarre that anyone would want to restrict themselves so much as to just drink shakes or juices or just eat cereal-type bars and omit all of the tasty, wholesome foods that they really can enjoy guilt-free. My ethos is to never skip meals, ignore hunger or restrict yourself so much that you feel deprived (most often this leads to binge eating, low mood and a lack of energy). Most importantly you need to nourish your body and consume adequate calories so that your metabolism doesn’t grind to a halt and so that your body can function optimally.

Dangerous Ingredients

Often the main ingredient in meal replacement bars and shakes or ‘detox’ juices is sugar. It may be labelled as syrup, dextrose, glucose, sucrose or maltose, to name but a few sugar pseudonyms, but it’s all the same thing. You may only be having 200 calories three times each day but the majority of these come from sugar, providing no nutrients whatsoever. The sugar rush you’ll experience after a shake or bar will give you enough energy to get through your day, but you’ll experience energy slumps, tiredness and mood swings. As your body tries to process this sugar it will release large amounts of insulin and, in turn, store the excess in your liver and muscle tissue.

Another ingredient commonly found in meal replacement bars and shakes is aspartame, a chemical sweetener known as a neurotoxin which has been linked to a range of unpleasant symptoms including migraines, muscle spasms, irritability and cognitive impairment. These occur because the hypothalamus (an area within the brain) cannot function properly when aspartame is present in the body and this can lead to hormonal imbalances. Aspartame is technically not sugar, and therefore companies are allowed to label products as ‘sugar free’ despite them being loaded with the chemical.

Slow Metabolism

Many people describe a feeling of euphoria and very high energy when they embark on a restrictive diet such as a shake diet. This is due to the endorphins released as a protective measure to ‘push you through’ the starvation period that your body perceives. Remember, we’re programmed to hold onto fat during periods of starvation as a survival mechanism and so that we can still ‘fight or flight’ even without many calories being consumed. Although you know that you are not exactly starving, your body doesn’t and so slows down your metabolism and stops performing functions around the body in an attempt to preserve energy.

Lack of Nutrients

It is a simple fact that your body cannot function properly without adequate nutrition. We need to eat foods with a wide variety of vitamins and minerals in order to avoid deficiencies which can cause hormonal imbalance, skin problems, migraines, nausea, irritability and so on. It is vital that we eat a range of fruits and vegetables, pulses, grains, dairy, meat, fish or soy products in order to obtain these nutrients and allow our body to adequately function.

In terms of fat, you need to eat fat to lose fat. Of course that’s not to say a litre of ice cream will help you to shed the pounds, it’s about the type of fats you eat. Omegas 3 and 6 – found in eggs, flaxseeds, rapeseed oil and oily fish – are an essential component of any diet, even if you’re trying to lose weight. Extra virgin olive oil, avocados and unsalted nuts – such as Brazils and almonds – provide equally important essential fats (the unsaturated variety, as opposed to saturated). In short, it is a myth that cutting out fat from your diet will help you to lose weight more quickly or keep it off in the long term.

Being on a meal replacement diet will also mean you’re missing out on fibre which can result in bloating, sluggish digestion, constipation and low energy. In the long term a lack of fibre can even contribute to the development of bowel cancer. Fruit, vegetables, pulses and wholegrains all contain fibre and must be consumed every day to keep your digestive system healthy and your energy levels up.

Safe, Healthy Weight Loss

If you do want to lose weight and keep it off, the message is to stick to a steady pace. Never ignore hunger or skip meals as this will slow your metabolism right down. On average, women should never reduce their calorie intake to below 1,200 and men below 1,800 (a GP may advise differently depending on your circumstances). Again this is to avoid your metabolism slowing down and to provide your body with adequate energy. No food group should be cut out completely, although sugar should be avoided (unless it’s naturally occurring in fruit and vegetables) and saturated fat should be reduced to no more than 30g for men and 20g for women each day. Unsaturated fats such as those in extra virgin olive oil, oily fish, nuts and avocados should be reduced to no more than 60g for men and 50g for women each day. You should aim for a weight loss of 2lbs per week if you're overweight and up to 4lbs per week if you're obese.

A typical, healthy day on a weight loss diet could look like this:

Breakfast – 2 slices wholegrain toast with marmite or nut butter.

Lunch – 1 avocado with salad and 2 oatcakes / 1 tin tuna in spring water with salad dressed with lemon juice and 1tbsp extra virgin olive oil plus 2 oatcakes.

Dinner – 1 chicken breast or 1 Quorn fillet or ½ block tofu, stir fried with vegetables and 1 serving spoon brown rice.

Snacks - Natural yoghurt with strawberries and 1tsp pumpkin seeds / 1 banana plus 10 almonds / ½ pot cottage cheese with 2 rice cakes.

I really do advise that you avoid any meal replacement diet. The effects that they have on your body are not worth any rapid weight loss you might achieve (note: rapid equals short term). Take it slow, enjoy food, be mindful of your portion sizes and don’t restrict or deprive yourself!