Doctor Reviews: PhenGold - Dr. Brian Yeung, ND (2024)

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PhenGold is a branded combination supplement promising to “burn fat and boost metabolism”. But does it actually work? And is it safe to use?

Let’s comprehensively review PhenGold for weight loss to see if it’s worth your money, see if we can replicate it with a cheaper alternative, and give it an overall rating.

Ingredients of PhenGold

Let’s take a look at the ingredients. Here are the doses per capsule. The recommended dosing is three capsules a day.

B vitamins

Let’s start with the B vitamins. The B vitamins, particularly Vitamin B12, B6, B5, and B3, are used by your body to help break down food and convert it into energy.

Supplementing them is really only useful if you’re at risk of being deficient in these nutrients. Taking more than your body actually needs is not going to cause you to lose more weight, or more efficiently burn energy.

The B vitamins are found in all kinds of whole grains, vegetables and animal protein, and if you’re eating most of these foods, chances are you’re not deficient.

However, B12 is found mostly in animal protein, so if you’re vegetarian or vegan, or just have a diet low in animal protein, supplementing B12 is sometimes a good idea, especially in those who are older.

That being said, the B vitamin doses in PhenGold are really weak. People deficient in B12 usually supplement B12 at 1000 mcg per day, not 24 mcg per day. So you’ll do much better taking a good quality B complex supplement if you were actually deficient in any of the B vitamins.

Green tea and green coffee

Whenever supplements add green tea and or green coffee extracts to their product, they like to use the claim that their product is now “thermogenic”, and helps to burn fat.

Unfortunately, studies do not show any significant weight loss from these supplements, and I find that it’s often the caffeine content from drinking green tea or green coffee that helps people to exercise more, which results in any noticeable weight loss.

Of course that means for these to work properly, you’ll need to actively exercise more and burn more calories, but this might not matter since the specific extracts they’re using are not effective.

Green tea extract is usually dosed at around 500 mg, standardized to a specific polyphenol called EGCG. All they’ve listed here is 50% polyphenols, which tells me they likely didn’t bother to standardize the active polyphenol, EGCG, so although the dose is sufficient, the extract they’re using here is not effective.

The same goes with green coffee. Green coffee extract is usually dosed at around 500 mg, standardized to a specific compound called chlorogenic acid. There’s no standardization here, and the dose is also too low, so I wouldn’t expect this ingredient in PhenGold to do anything.

L-Tyrosine

Next is L-tyrosine, which is an amino acid. This is interesting, because tyrosine is not something I see in a typical weight loss supplement.

This is because tyrosine has absolutely no known effects on weight. Rather, it’s known as a supplement to help with cognition and memory.

The fact they’ve added it here starts to tell me the type of supplement they’re trying to put together here, maybe something more for energy and wakefulness.

Unfortunately the dosing here is way too low. We’re looking for a few grams of L-tyrosine per day, and 300 mg ain’t gonna cut it.

But perhaps they’re leaning more towards increased energy and wakefulness. We’ll check out the other ingredients to see.

Rhodiola and L-theanine

Taking a look at the next two ingredients seems to confirm my suspicions. Rhodiola and L-theanine are used for their possible effects on cognition and wakefulness.

There are no known direct effects on weight loss, however, they are recognized for their possible use to help people manage stress.

Additionally, the dosing and standardization used is sufficient, making me start to think this supplement may be more useful for stress and cognition, than it is for weight loss.

Dimethylethanolamine (DMAE)

Dimethylethanolamine (DMAE) also falls into this group, and is a supplement that was once marketed for children with ADHD, as it shows some weak evidence for its nootropic effects.

A nootropic is something that might be able to help improve brain performance and cognition, and DMAE might be expected to also help with cognition however, the dose is too low in PhenGold as studies typically dosed around 500 mg of this stuff.

Caffeine

When we combine these ingredients with this supplement’s likely main active ingredient, caffeine, which is yet another nootropic and cognitive aid, we can see what kind of supplement this really is.

This part is likely what makes the supplement work for some people, as caffeine does have some potential uses for weight loss, mostly in the form of increasing wakefulness and alertness, helping people to remain more active and exercise more.

PhenGold gives you 225 mg of caffeine, equivalent to about 3-4 shots of espresso, which is a moderately strong dose.

Cayenne extract

Finally we have cayenne extract, which is essentially a crude form of capsaicin. I’ve talked about capsaicin for weight loss before, but to summarize, capsaicin might be slightly helpful for weight loss when used as a spice in food, when you can taste it, since the burning sensation might make people eat less and drink more water.

But as a supplement, and especially at the tiny dose in PhenGold, it’s totally useless.

BioPerine®

Bioperine is a standardized pepper extract and in this case it’s used to help improve the absorption of some of the other ingredients like caffeine, but otherwise it has no therapeutic effects.

PhenGold Side effects and concerns

So is PhenGold safe to take? Well the most concerning is likely the caffeine content.

If you’re sensitive to caffeine, have cardiovascular issues, anxiety disorders, or are taking other stimulant drugs like phentermine, you need to ask your doctor to see if it’s safe to take.

This is also not safe for pregnancy or if you were breastfeeding.

I would not take more than 4 capsules per day or you might start getting symptoms of caffeine overdose like anxiety, headaches, or dizziness. I would also avoid taking it in the evening, or it might cause insomnia.

Is PhenGold effective?

Taken together, PhenGold is not really a weight loss supplement. Rather, it seems to be trying to create a supplement that supports cognition and alertness.

If PhenGold was used for weight loss, it would be mainly as a supplement to increase wakefulness, and improve your energy for exercise, mainly thanks to all that caffeine.

This means that you would need to exercise more frequently, and with greater intensity while on the supplement for it to be useful at all.

The name PhenGold likely plays off the popular drug phentermine, which is a stimulant drug. PhenGold contains no phentermine, and is also not going to work at all like phentermine.

So while PhenGold could be considered a stimulant, it’s not going to be the type of stimulant that’ll help you burn fat and boost metabolism like they advertise.

Rather, it works by making you feel more awake, so that you might be inclined to exercise more and do more physical activity.

Overall review: PhenGold

Reviewing PhenGold by effectiveness for weight loss, I’m giving it a C. It basically works as an exercise aid, and taking it without increasing your exercise is not likely going to have any effects on weight whatsoever.

Reviewing PhenGold by cost, I’m giving it a D. A monthly cost of $75 is a little steep, and it can be essentially replicated by getting individual ingredients at a cost many times less.

Reviewing PhenGold for safety, I’m giving it a C. It’s not safe for everyone to use due to the high caffeine content.

Overall review, I’m giving PhenGold a D. I would not recommend it at all.

Top alternatives to PhenGold

Overall, PhenGold is an overpriced caffeine pill, with some added nootropics like rhodiola and L-theanine.

Like most caffeine supplements, it can help to improve your energy and increase the frequency and intensity of your exercises.

PhenGold tries to combine a few other helpful ingredients. However, the doses and ingredients that it uses effectively limit it to just a rhodiola, L-theanine, and caffeine supplement.

If you’re looking to achieve similar effects, but better than those of PhenGold, I would combine a quality green coffee or green tea extract + rhodiola + L-theanine + caffeine.

• Caffeine anhydrous – 1 cap / day
• Green coffee (caps) – 1 to 2 caps / day
• Green tea (caps) – 2 to 4 caps / day
• Green tea (teabags, decaf) – 1 to 4 cups / day
• Green tea (teabags) – 1 to 4 cups / day
• L-Theanine – 2 to 4 lozenge / day
• Rhodiola – 1 cap / day

Learn more about

• Is Caffeine Good For Weight Loss?
• Green Tea For Weight Loss
• Green Coffee Bean Extract For Weight Loss
• Capsaicin For Weight Loss
• 6 Things To Look For On Supplements
• 5 Things to Know Before Buying Weight Loss Supplements
• Other weight loss supplements

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Attributions

“File:Human gallstones 2015 G1.jpg” by George Chernilevsky is licensed with CC BY-SA 4.0. To view a copy of this license, visit https://creativecommons.org/licenses/by-sa/4.0

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