In consideration of the topic, here are the 3 main questions to answer:

'Do Slimming Teas actually result in weight loss'; 'Are they safe to consume'; and 'What possible harmful effects could they cause in the short to medium term'?

Do Slimming Teas actually result in weight loss?

There are hardly any robust, extensive or large studies that show a direct effect between slimming teas and weight loss.

Most of them purport to contain herbs or supplements which have been shown to increase metabolism and by so doing weight loss. but outside of small studies or those conducted by the product manufacturers, this has not been validated.

However, taking slimming teas can lead to an increase in the gastric function and further purging.

As they are taken in the form of fluids, this contributes to increased urination, which in addition to purging effect of the components of the teas, causes some apparent ‘weight loss’.

Being composed of largely to fluid, this weight loss is not sustained.

Are Slimming Teas safe to consume?

The issue of safety is important.

Many teas that are taken for weight loss contain herbs as the principal-agent in addition to the tea.

The problem with this is that not enough studies have been done to study the effect on these additional herbs when taken on their own; or when they are combined with the daily consumption of any other medication the individual user is on; or even how they may affect people with medical conditions such as asthma, hypertension etc.

As a result of this, it is difficult to say with certainty that they are safe.

What possible harmful effects could they cause in the short to medium term ?

Harmful effects from using the slimming tea depend on its individual ingredient.

So for those which have purging properties (laxatives), the following will result:

• Stomach pain,

• Diarrhoea,

• A weakness of the bowel muscles leading to sluggish bowels,

• Electrolyte imbalances which can lead to other serious complications.

For slimming teas that contain herbs with diuretic actions (a diuretic is a drug that promotes loss of fluid from the body); they can also cause side effects or complications.

While this diuretic property can be useful - for example - some drugs used in treating medical problems like heart failure; however, when used without restrictions or quantities that are not controlled, it can lead to

• Dehydration,

• Muscle cramps and

• Electrolyte problems.

The last word

So to conclude, dietary supplements like ‘slimming’ tea have not been shown to be directly linked to weight loss.

The American FDA (Food and Drug Administration) warn against the use of most dietary supplements, including slimming teas, mainly due to a lack of reliable studies and evidence of their safety or effectiveness.

However, we should say that some types of tea - not necessarily the ‘slimming’ type can confer benefits such as antioxidants which help to prevent cancer.

https://www.healthline.com/nutrition/top-10-evidence-based-health-benefits-of-green-tea#section1
There are also some studies that suggest that green and black tea can help with weight loss

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4991829/

Therefore instead of relying on 'slimming teas' that do not have benefits, weight loss can be achieved safely by a number of different methods over time:

• A healthy diet that is low in processed food, low in sugary foods and drinks but loaded with fiber, proteins and good oils

• A regular exercise programme - especially with weight training which is the surest way to ensure fat burning.

• Regular rest and sleep which reduces stress hormones that can affect weight gain.