Diet Pills: Are They EVER A Good Idea?

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  • There are lots of weight loss supplements on the market that claim they can help you shift the pounds faster. But do they actually work? And are they even good for you? Here's the expert verdict...

    We’ve spoken to expert nutritionist Dr.Marilyn Glenville to find out whether taking diet pills is ever worth it…

    ‘There are some diet pills on the market that are touted as helpful with weight loss but I do have concerns with them,’ she says.


    This is a Chinese herb, also known as ephedrine and ma huang, which has been used in diet pills because it has a stimulant effect. It can cause an increase in metabolism but the stimulant effect also causes an increase in heart rate and blood pressure. These side effects have been associated with strokes and heart attacks. Other side effects can include irritability, anxiety, skin reactions, trembling and sweating.


    This is a plant that is found in Brazil. Like ephedra, it is used for its stimulant effect, as its caffeine content is twice that found in coffee beans. Side effects can include anxiety, irritability, increased heart rate, sleep problems, dry mouth, heartburn and trembling.

    Raspberry Ketones:

    Raspberry ketones also occur in cranberries and blackberries. But the level naturally occurring in fruit is very low so it has to be made industrially in order to achieve a concentrated level. There is much publicity surrounding raspberry ketones and their ability to help you lose weight but, looking at the evidence, there has been no research on humans as to their effectiveness and only two studies on mice. Side effects can include jitteriness and anxiety. I would be especially careful if the diet supplement also contains other stimulants like caffeine because the side effects can be stronger.

    So is there a better alternative? 

    ‘Food is the foundation of health and you need to eat right in order to lose weight. A number of chemical reactions are involved in turning glucose into energy instead of fat, and certain vitamins and minerals do help this to happen. If you are deficient in these nutrients, the body will find it harder to let go of weight.

    Supplements can be used alongside a healthy diet to make the food side of things more effective but won’t replace eating well. These supplements should really just be more of the same nutrients that you can get from food. 

    The most useful nutrients for weight loss are: 


    Helps control cravings and binges. 


    Helps balance blood sugar by contributing to the production and action of insulin.

    B vitamins:

    Help food turn into energy instead of being stored as fat. 

    Alpha lipoic acid:

    Release energy by burning glucose so less fat is stored. 

    Amino acids:

    Have fat-burning benefits and also help control appetite. 

    But ultimately, eating well is the only thing that will work long-term…

    ‘If someone is really serious about losing weight (and, more importantly, fat) then they need to think about food and eating as a way of life, so that healthy, enjoyable eating becomes a habit – something you do everyday without even thinking about it, just like cleaning your teeth.

    People should aim to eat well 80 per cent of the time. No one is perfect and we don’t need to be to achieve our weight-loss goals. Be kind to yourself and let go of the other 20 per cent.’

    Here are 5 supplements that have the Marie Claire seal of approval…

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