I used to be a sucker for anti-wrinkle creams (bear with me, I’ll get around to the weight loss tablets). Anything that claimed to reduce the appearance of wrinkles captured my attention immediately. And if they were ‘clinically proven’ to ‘work’, I was sold.

They maybe did make a difference to my wrinkles, but I think the difference was only visible under a microscope. Bottom line, the products appealed to a ‘flaw’ and I bought them, with what I now know to be unrealistic expectations.

So now to the pills…Taking a pill to help with weight loss is a very attractive idea. Weight loss tablets make bold claims about what they can help you achieve, but I haven’t seen any that are upfront in telling you just how much weight you can expect to lose. In the absence of this information, we purchase in blind hope and probable unrealistic expectations.

This article will look at the following substances with alleged weight loss benefits:

caffeine
carbohydrate blockers
conjugated linoleic acid (CLA)
fat binders
garcinia cambogia
glucomannan
green coffee bean extract
green tea extract
guarana
raspberry ketones

Each of the above will be examined under the following headings:

What is the active ingredient?
How is it meant to help me lose weight?
How much weight might I lose?
What are the potential side effects?
Product examples
Price range
Verdict

It’s a long article, so feel free to go straight to the sections that are of most interest to you and bypass the rest. Here goes…

Caffeine

What is the active ingredient?

Caffeine!

How is it meant to help me lose weight?

Caffeine is a stimulant that can increase metabolism (the amount of calories ‘burnt’), and release fat from fat stores to be available for energy.

How much weight might I lose?

Caffeine has been shown to improve athletic performance – having fat stores available for energy is a good thing if you’re an athlete. But I’m guessing you’re not an athlete.

With regard to weight loss, there is no evidence that caffeine can help with weight loss in the long term. Long term use leads to caffeine tolerance when any additional boost to metabolism or effect on weight stops.

What are the potential side effects?

Insomnia, nervous, restless, irritated, stomach upsets, nausea, vomiting, diarrhoea.

Product examples (some are in combination with other ingredients)

Grenade Thermo Detonator | Holland and Barrett Xtralean Capsules | JST Jodie Marsh Semtex Capsules | PHD Woman Body Sculpt | Slim Zest T5 Rapid Burner

Price range

£15 – £45 for 1 month’s supply

Verdict

If you’re serious about your athletic performance, maybe. If you’re not being active, any fat released from fat stores will be sent back to fat stores if the energy is not being used, so its effect on reducing body fat will be minimal.

Carbohydrate blockers

What is the active ingredient?

This is usually a substance from beans such as white kidney bean extract.

How is it meant to help me lose weight?

These products slow down the action enzymes that digest carbohydrate. If less carbohydrate is digested, less is absorbed, and you may ‘lose’ up to 200 calories worth of calories per day.

How much weight might I lose?

Studies show mixed results, ranging from 1lb weight loss after 4 weeks of use, to 8lbs after 12 weeks of use.
These products usually only affect the breakdown of complex carbohydrates (which are broadly those found in cereals, breads, pasta, potatoes or rice for example). They will have less effect on the absorption of simple sugars, such as table sugar, confectionery, bakery products or sweetened drinks for example.

What are the potential side effects?

Diarrhoea, bloating, wind, cramps. Avoid these products if you have IBS, and use with caution if you are using diabetes medications.

Product examples (some are in combination with other ingredients)

Boots Carb Control | Holland and Barrett Carb Minders | Innopure Metacarb | XLS Max Strength Powder

Price range

£25 – £90 for 1 month’s supply.

Verdict

These can be expensive products for the weight loss outcome. 200 calories is roughly equivalent to 2 slices of bread. May be more economical to save £25 – £90 a month and reduce carbohydrate intake by 200 calories / day.

Conjugated Linoleic Acid (CLA)

What is the active ingredient?

CLA

How is it meant to help me lose weight?

CLA is reported to reduce appetite, boost metabolism, and block an enzyme that promotes the absorption and storage of dietary fat, thereby reducing body fat.

How much weight might I lose?

Some studies show a ‘small’ amount of body fat loss in the region of 0.05 – 0.09kg per week (1/5 lb!), up to a maximum of 2.5kg (5.5 lbs) fat loss after 2 years. Other studies show no effect.

What are the potential side effects?

Bowel alteration, stomach pain, nausea, increased inflammation and potential increased insulin resistance.

Product examples (some are in combination with other ingredients)

Forza CLA 1000mg | Iron Ore Health Energising CLA | Lean Nutrition CLA 1000mg | PHD Women CLA | USN Phedra Cut Lipo XT Fat Burner

Price range

£12 – £45 for a months supply

Verdict

5lbs weight loss for a spend of £290 – £1,120 over 2 years? I think not.

Fat Binders

What is the active ingredient?

This varies from Orlistat, Captoglicolipid, or fibres such as Chitosan.

How is it meant to help me lose weight?

These ingredients block either the breakdown or absorption of dietary fats.

How much weight might I lose?

A 12 week study showed an additional weight loss of 2.5kg / 5lbs when using a fat binding product.

What are the potential side effects?

Bowel alterations, from oily discharge to diarrhoea.

Product examples (some are in combination with other ingredients)

Alli Hard Capsules | Boots Pharmaceutical Fat Control | Fat Blaster Fat Magnet | XLS-Medical Fat Binder | XLS-Medical Fat Binder Direct Sachets

Price range

£20 – £60 for 1 month’s supply

Verdict

These tablets trump card is in their deterrant effect. People are often able to ‘stick’ to a low fat diet to avoid side effects. But then, if you follow a low fat diet, you may lose some weight anyway without the tablets.

Garcinia Cambogia

What is the active ingredient?

Hydroxycitric acid

How is it meant to help me lose weight?

Hydroxycitric acid is reported to suppress the appetite, but how it is supposed to do this is unknown. It is also thought to influence enzymes which have a role in fat breakdown and production of new fat cells.

How much weight might I lose?

Some studies show that garcinia cambogia can cause weight loss of around an additional 2lbs. Other studies show no additional weight loss.

What are the potential side effects?

Digestive problems, headaches. May increase serotonin levels so it could interact with some anti-depressant medication.

Product examples (some are in combination with other ingredients)

Price range

£10 – £40 for 1 month’s supply

Verdict

Given potential side effects and small weight loss, this is not worth it.

Glucomannan

What is the active ingredient?

Glucomannan (from the Konjac plant) is a soluble fibre.

How is it meant to help me lose weight?

Glucomannan absorbs a lot of water (up to 50 times its weight). This fills the stomach and slows down stomach emptying which keeps you feeling full for longer.

How much weight might I lose?

Studies show that adding glucomannan to your diet gives an additional 0.4 – 0.8kg (0.8 – 1.8lbs) of weight loss per week.

What are the potential side effects?

Generally safe when used as directed. Do not use if you have IBS.

Product examples (some are in combination with other ingredients)

Price range

£11 – £55 for 1 month’s supply

Verdict

Glucomannan is the only supplement approved by European Food and Safety Authority as a weight loss aid. If you struggle with frequent hunger, or find it hard to reduce portions, then glucomannan products may help.

Green Coffee Bean Extract

What is the active ingredient?

Chlorogenic acid

How is it meant to help me lose weight?

Chlorogenic acid reduces the breakdown and absorption of carbohydrate and some report it suppresses appetite and boosts metabolism.

How much weight might I lose?

Studies show weight loss benefit ranging from 0.3kg / 0.7lbs after 1 month to approximately 3.7kg / 8lbs after 3 months of use.

What are the potential side effects?

Green Coffee Bean Extract appears to have a good general safety profile.

Product examples (some are in combination with other ingredients)

G-Biotics Green Coffee Bean Extract | Holland and Barrett Green Coffee Bean Extract 400mg | Nature’s Way Green Coffee Bean Extract

Price range

£15 – £25 for 1 month’s supply.

Verdict

I’d be pretty cross if I spent £25 to lose an extra 0.7lbs in a month.

Green Tea Extract

What are the active ingredients?

Epigallocatechin gallate (EGCG), catechins, caffeine

How is it meant to help me lose weight?

Green Tea Extract is alleged to influence hormones that help to burn fat and control hunger.

How much weight might I lose?

Studies show about a 1kg / 2lbs weight loss after 12 weeks of use.

What are the potential side effects?

Abdominal discomfort, constipation, nausea, and risk of raised blood pressure.

Product examples (some are in combination with other ingredients)

Price range

£2 – £25 for 1 month’s supply

Verdict

2lbs weight loss after 12 weeks? Not worth it.

Guarana

What is the active ingredient?

Caffeine (guarana contains twice as much caffeine as a coffee bean)

How is it meant to help me lose weight?

Caffeine is a central nervous system stimulus, which increases metabolism and increases adrenalin, which results in release of fat from fat stores to be available for energy.

How much weight might I lose?

A study about Zotrim (contains guarana, yerba mate and damiana) showed weight loss of 4.5kg after 45 days, but no further weight was lost despite ongoing use for 1 year.

What are the potential side effects?

Insomnia, nervous, restless, irritated, stomach upsets, nausea, vomiting, diarrhoea.

Product examples (some are in combination with other ingredients)

Holland and Barrett Super Guarana 1200mg | Met-Rx Xtreme Thermo Crush | Zotrim Herbal Weight Loss Aid

Price Range

£12 – £25 for 1 month’s supply

Verdict

A weight loss of 4.5kg / 10lbs is reasonably impressive. Bear in mind though that the study participants were also on a diet programme. And what would happen if the tablet was stopped after 45 days – would the weight be regained? If the tablet needs to be continued indefinitely to maintain the weight loss, the yearly cost would be in the region of £300 per year.

Raspberry Ketones

What is the active ingredient?

Synthetically produced Raspberry Ketones

How is it meant to help me lose weight?

Raspberry ketones increase the breakdown of fat and regulate metabolism…in rats. Its action on humans is hypothetical.

How much weight might lose?

There are no good human studies using raspberry ketones, so this is anybody’s guess.

What are the potential side effects?

Raspberry ketones are approved as a food additive so it is generally safe. However, this will be at much lower levels than that found in supplements. Given the lack of studies, the safety profile of raspberry ketones at doses used in supplements is unclear.

Product examples (some are in combination with other ingredients)

Price range

£5 – £35 for 1 month’s supply

Verdict

If you’re an overweight rat, go for it.

To sum it all up….

If you only have a few stubborn pounds to lose, you will probably achieve that with any of the above supplements combined with healthy eating and exercise.

My guess is that the majority of weight loss supplements are purchased by people who want to lose significantly more than a few pounds. Unfortunately, weight loss supplements are highly unlikely to help you achieve this.

Like diets, weight loss achieved while using a tablet does not mean that the weight will stay off when the tablet is stopped. You are unlikely to be willing to buy any product forever, just to keep off a few pounds.

If you struggle with your weight, the problem is likely to a combination of food choices, unhelpful food behaviours, maybe yo-yo dieting, and possibly some underlying problem with hormones that affect weight. No pill will address these problems.

There’s no doubt you could spend a lot of £’s, but don’t get your hopes up about losing the same amount of lbs.