Diet and weight control- which diets work?

Fiona Clark

 Diet and weight control- what works and what’s dangerous? Dietitian Sophie Medlin explains.

Social media is flooded with diets that promise to shed pounds off you instantly or help you live longer – but what do the experts think?

Dietitian Sophie Medlin, founder of City Dietitians in London says fads come and go but very few are effective and some can even damage your health.

Some of us may have long term issues with our weight and others may be worried after adding a few extra pounds (or kilos) during lockdown. But, as Sophie says, we are in the middle of a global pandemic which means most of us are at home and may be comfort eating.

In addition we’re doing less incidental exercise – walking to the bus stop or train station. Gyms are shut as well. So our energy output may be far lower than usual.

And then, as Sophie explains, stress can also play a part in weight gain. She says worring about our health, jobs and future could mean many of us are experiencing higher than usual levels of stress. Stress causes us to release more cortisol which is a ‘fight or flight’ hormone that tells the body that it needs to ‘fuel up’ ready to run or battle, so you may feel that you need to eat more.

The Stress factor

While sudden trauma’s may raise stress levels and cause you to loose weight, exposure to stress over the long term (chronic stress) acts in the opposite way and may result in weight gain.

“So at the moment there are physiological reasons for why we’re hungrier at the moment, and then there are environmental reasons as well that are affecting our food choices. We’re living out of our pantries. So we shouldn’t be too hard on ourselves,” she says.

Instead we need to look at our relationship with food and recognise what triggers our eating and food choices, and devise strategies to change those is a sustainable way.

“It really is just a case of thinking about your relationship with food. So, if you notice that you’re eating because you’re stressed then think about other things you can do that lower your stress hormones. It might be something as simple as stretching by your desk, going for a little walk or making a nice cup of tea – anything you can do that makes you feel calmer can help you manage your food intake. Stress management is really key.”

What about diets?


Keto Diet? 

This was originally designed to help reduce the incidence of epileptic fits in children, Sophie explains, but when it comes to weight loss many people may find it unsustainable.

Yes, reducing the carbohydrates and can help with weight loss, Sophie says, but for many people it’s not enjoyable and sets them up for a fall.

“If you can do it and don’t feel like you’re being deprived, then it’s fine, but I think you’re better off thinking about reducing carbs slightly and eating a well balanced diet with plenty of fruit and vegetables. That way you’re less likely to feel deprived and give up,” she says.

When we try and diet and it doesn’t work we feel like we’ve ‘failed’ and she says that’s not helpful.

“We want to feel empowered, because if we start a diet and we lose weight and then we put it on again, we feel like rubbish and we get into the vicious cycle of  yo-yo dieting.

“You know, I’ve seen women in my clinic who’ve done this for 30 years and they still hate their bodies, they’re still unhappy and spend hours worrying about what they eat everyday.

“One thing I talk about with my clients is how much mental energy we waste wanting to be thinner. If you put that energy into things you love – hobbies, careers, relationships, those things will grow. But this obsessive thinking about our weight is wasting people’s lives.”

“I’m not saying obesity is benign, because it does have an impact on our health, but that yo-yo dieting and constant obsession with our food can also have a detrimental effect on us. There has to be a balance between those two things,” she says – and this comes down to the relationship we have with our food.


Detox Diets?

“Anything that has the word detox in it is a marketing scam. The only thing that is going to detoxify you is your liver and your kidneys. Obviously having a really bad diet can impact on your liver and kidneys – but if they aren’t working you need to go to a hospital, not buy a juicer and juice book.”

“Juicing will basically mean that you’ll end up becoming deficient in things like amino acids very quickly. It’s not giving your body the nutrients it needs and it’s not sustainable. Just think about sensible, sustainable eating.”


Removing Sugar from the diet?

“Free sugar- or sugars that we add, including date sugar or maple syrup – any sugars we add ourselves to sweeten things we need to be a be more careful with,” she says.

But if it comes to removing foods like fruit because they contain natural sugars, then it’s gone too far.

“Fruit is always good for us. There is no reason to cut that out. Obviously if you’re eating loads of dried fruit or drinking a lot of fruit juice that could be an issue, but if you’re eating sensible portions of fruit every day, that’s not an issue.

“The food industry obviously adds sugar to foods and you should be conscious of that, but if you’re cooking at home it shouldn’t be a concern,” she says.

“The reason why we worry about sugar is when people are eating sugary cereals and sugary drinks for breakfast, and lunch – that’s when we are concerned. But people who are eating fruit and giving fruit to their kids shouldn’t worry. It’s a misinterpreted message.”

Removing fruit from the diet means you miss out of vitamins, minerals and fibre – and that could put your health at risk.

“I hear people talking about sugar as ‘toxic’ and that’s a far more toxic message than the sugar is.”

Adults and children should aim to have at least two portions of fruit a day and 3 of vegetables.


Intermittent fasting?

“Intermittent fasting has some great evidence behind it for weight loss. There are various patterns  like the 16/8 where you eat between an 8 hour window and fast for the rest of the time, or you may want to restrict calories for 2 or so days a week,” she says.

May fasts now come with meal replacements, but Sophie says there are some important considerations when using these.

“The things like shakes that may go with these diets are generally used as meal replacements of the days when you’re restricting calories. And there is good evidence for these particularly in people who have type 2 diabetes. But it really must be done under supervision of a dietitian or a medical team because you may be missing out on the nutrients you need and also because it’s very hard to re-introduce foods and maintain a normal relationship with food if they’ve been doing this for a while,’ she says.

“I’d really encourage people to try 16/8 as a pattern of eating if they think it might work for them, or the 2 days of 500 calories or so a day if that would suit them better.”

And she adds, the jury is still out when it comes to many of the claims made about fasting such as longevity or reducing the risk of cancer.

“It’s important to remember that the only thing you’ll gain from fasting is losing a bit of weight – all the other benefits that are claimed for it are massively overstated and are derived from studies in mice or cells lines – and we are not mice or cell lines in a dish. These findings haven’t been translated to humans yet.”


The skinny jab?

These are injections of a medication called liraglutide that was designed to treat people with type 2 diabetes and later licensed for use in obese patients. There are a few brands on the market now being touted as weight loss products but it is not something Sophie recommends.

“These are a special type of medicine that are used for treating people with diabetes,’ Sophie says. “They are now being marketed as a way to lose weight without having to do anything else. But the data from studies looking at people who have used the jab and a diet or the diet alone lost very similar amounts of weight. It was statistically significant but not clinically significant or weight that you’d notice,” she says.

“You still have to follow a healthy diet and I would just massively discourage people from using jabs as they can have side effects and once [the medication] is in, you can’t get it out. And please, don’t take advice from influencers on weight loss or jabs like this,” she warns.

“The side effects can be horrible and we don’t know the long term effects are, she says. It can cause headaches, diarrhoea, pancreatitis, confusion and dizziness and heart palpitations – among other things.

“What we do know is that eating sensibly and sustainably and getting a bit of exercise each day can make a difference and is much safer.”

Many influencers tout the products saying they can now eat anything they want – but this is not a healthy way to live and could have other flow on effects that could affect your health later on in life.


Supplements to suppress appetite?

There are some, Sophie says, but it’s probably better to “focus on eating things that make you feel fuller like proteins or high fibre foods, or yoghurt – things that are going to make you feel fuller for longer.”

There are products that bloat up in your stomach or restrict your absorption of fat and give you diarrhoea, “but is that really what you want?”

And once you stop, any weight you’ve lost will come back on, and you’ll be back to square one – unless you change your relationship with food.


If you need help you can find Sophie Medlin at City Dietitians  and you can watch the video of our interview here.

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