Do I need supplements? Most people do not. Four have decent evidence behind them for general training and health: protein powder, creatine monohydrate, caffeine, and vitamin D for people a blood test shows are low. Mr PT Fitness is a private home studio at 35 McIntosh Road, Dee Why, run by Matt Reilly, a personal trainer with 10+ years' experience, and this is the answer clients get here before they spend anything. A supplement is designed to fill a specific gap in a diet that is already mostly working. It cannot fill a gap where the diet is not working, and no powder has ever rescued a training week that did not happen.
Do you actually need supplements?
No. Most people do not need supplements, because a supplement exists to fill a named gap in an otherwise reasonable diet, and most people asking the question cannot yet name their gap. If you do not know what your daily protein intake is, a protein powder is a guess wearing a label.
The question almost always arrives at the wrong moment. Someone starts training in Dee Why in week one, training is still irregular, dinner is whatever is fastest, sleep is six hours, and the first thing they want to talk about is what to buy. The supplement is the smallest lever on the table and it gets reached for first, because it is the only one you can solve with a credit card in four minutes.
Put a number on it. Across a year, the things that decide your result are how many sessions you actually did, how much protein and how many vegetables you ate, and how you slept. Supplements sit somewhere in the last few percent. A few percent is worth having once the rest is in place, and worth nothing when it is not.
The honest test before buying anything is one sentence: what gap is this filling, and how do I know I have it? If you cannot answer, that money is better spent on food or on a session. Working out your protein target is a better first step, and the method for that is in how much protein do you need.
Which supplements have decent evidence behind them?
Four come up repeatedly: protein powder, creatine monohydrate, caffeine, and vitamin D for people who have tested low. Everything else on the shelf is either a version of those, or is sold on claims well ahead of what the research supports.
| Supplement | What it actually is | What the evidence generally supports | The catch |
|---|---|---|---|
| Protein powder | Dried milk or plant protein, in a tub | Helps people reach a daily protein target when cooking is not practical | It is food priced as a supplement. Whole food does the same job |
| Creatine monohydrate | A compound your body makes and you also get from meat and fish | One of the most studied sports supplements, generally associated with small gains in strength and training output | The effect is small and only shows up alongside consistent training |
| Caffeine | The same stimulant as coffee, sold in tablets or powder | Commonly associated with lower perceived effort and better output in a session | Tolerance varies widely, and an afternoon hit costs sleep, which costs more than it gave |
| Vitamin D | A vitamin most Australians get from sunlight | Relevant only if a blood test shows you are low | Supplementing without testing tells you nothing about whether you needed it |
You will notice there are no doses in that table. That is deliberate. Dosing sits outside what a personal trainer should be telling anyone, and it belongs with a pharmacist, a GP or an Accredited Practising Dietitian who can see your history, your medication and your bloods. Anyone in a supplement shop giving you a number without asking those questions is selling, not advising.
Protein powder is worth one extra line, because it is the one most people buy first. It is a convenience product. A scoop after a session in Brookvale on the way home from work is useful when the alternative is nothing until 8pm. It is not useful as an addition to three meals that already cover your target.
Not sure whether you have a gap at all?
Free 15-minute consult at the Dee Why studio. We will look at what you actually eat in a normal week first, and if a supplement turns out to be pointless for you, I will say so. Book here or call 0422 745 334.
What is mostly marketing?
Most of the aisle. Fat burners, BCAAs for anyone already eating enough protein, testosterone boosters, cleanse teas and everyday multivitamins all sell far better than the evidence behind them. None of these are the reason someone is or is not getting results.
- Fat burners. The active ingredient is usually caffeine with additions. Energy balance still decides what happens to body fat, so you are paying a premium for an expensive coffee.
- BCAAs. Three amino acids sold on their own. If you are eating enough protein across the day, your meals already delivered them, along with the other amino acids that were left out of the tub.
- Testosterone boosters. Marketing runs a long way ahead of the research here. Anything genuinely affecting your hormones is a medical matter for a GP, not a shelf purchase.
- Cleanse teas and "flush" products. Many act as a laxative or a diuretic. The number on the scale moves, body fat does not, and the effect reverses as soon as you drink normally again.
- Multivitamins on top of a varied diet. Insurance against a risk you may not have. Worth discussing with a GP if your diet is genuinely restricted, and largely redundant if it is not.
One Australian detail worth knowing before you read any label. Most supplements sold here are listed medicines carrying an AUST L number, which means the TGA has assessed the product for safety and quality, but not for whether it does what the packet says. Registered medicines with an AUST R number go through the higher bar. A confident claim on the front of a tub is not the same as a claim anyone has checked.
The practical filter is simple. If a product promises a result rather than describing an ingredient, treat the promise as advertising. Labels are easier to read once you know which lines matter, and the same skill transfers straight from the supermarket shelf.
Why does food come first, always?
Because food covers the same ground for less money, arrives with everything else the body needs alongside it, and builds the habits that are still working in twelve months. A supplement is a top-up on a foundation. Buy the foundation first.
Run the maths on the cost. A five-product stack bought online commonly sits between $80 and $120 a month, which is $960 to $1,440 a year. The same money buys a 1-on-1 session from $50 or small group training from $25 a person every fortnight, and a session that happens changes more than a tub that sits in a cupboard.
The order that actually works, for a client in Dee Why, Curl Curl or Collaroy alike, is the same every time:
- 1. Training you genuinely repeat. Two or three sessions a week you will still be doing in March.
- 2. Protein and vegetables at most meals. The single biggest nutrition lever for most people.
- 3. Sleep and daily steps. Both free, both bigger than anything in a tub.
- 4. Then, if a real gap remains, one supplement at a time. One change, so you can tell what did what.
That last point matters more than people expect. Starting four products in the same week means that if something improves, you have no idea which one earned it, and you are now locked into paying for all four.
What I cover at the studio is the training plus general nutrition guidance inside a personal trainer's scope. That means protein targets, meal structure, portions and shopping habits. The nutrition plan from $120 sits inside those lines, and exactly what it includes is set out in what a personal trainer nutrition plan includes. The 1-on-1 and small group options are listed under services.
When should you talk to a GP or a dietitian?
Any time the question is medical rather than a matter of convenience. Deficiency testing, medication interactions, pregnancy and anything connected to a diagnosed condition sit with your GP or an Accredited Practising Dietitian, not with your trainer. That boundary is a legal one, and it is also where you get a better answer.
Book the appointment rather than guessing if any of these apply to you:
- Ongoing tiredness, low mood or symptoms you want explained. That needs a diagnosis, not a tub.
- A vegan or vegetarian diet, where nutrients such as B12 and iron are worth testing properly.
- Pregnancy, breastfeeding, or trying to conceive.
- Any regular prescription medication, since interactions are real and a pharmacist can check them in minutes.
- A diagnosed condition of any kind, or a history of disordered eating.
Referring out is not a trainer passing the job along. A GP can test where a guess cannot, and an Accredited Practising Dietitian can write the medical nutrition side that sits outside a Cert IV scope. I would rather send someone up the road and keep doing the part I am qualified for well.
General information, not individual medical or dietary advice. See your GP or an Accredited Practising Dietitian (APD) for your situation.
Frequently asked questions
Do I need protein powder?
No. Protein powder is a convenience, not a requirement. It is dried food that helps people reach a daily protein target when cooking is not practical, such as straight after a session or on a long work day. If you already hit your target with meat, fish, eggs, dairy or legumes, it adds nothing except cost.
Is creatine safe?
Creatine monohydrate is one of the most studied supplements in sports nutrition, and research in healthy adults generally reports it as well tolerated. That is general information, not clearance for you. If you have a kidney condition, take regular medication, or are pregnant or breastfeeding, ask your GP or pharmacist before starting anything.
What supplements are a waste of money?
For most people: fat burners, BCAAs if you already eat enough protein, testosterone boosters, cleanse teas, and a daily multivitamin on top of a varied diet. These sell on promises the evidence does not support. Spend the same money on groceries, or on one extra training session a month.
Spend the money on the part that works
Free 15-minute consult at the Dee Why studio. We will sort the training and the food first, and only look at supplements if a real gap is left over. Clients come from Dee Why, Brookvale, Curl Curl and Collaroy.