A crowded, noisy aisle
Supplements are a multi-billion pound industry, and the marketing budget behind most products says nothing about whether they actually work. This lesson is a plain, evidence-based look at what genuinely has research behind it and what does not, so a supplement aisle stops feeling overwhelming.
Nothing here replaces real food, a calorie target, or the tools already covered in earlier lessons. At best, a supplement is a small edge on top of those things, never a substitute for them.
Genuinely well-supported
Creatine monohydrate
One of the most researched supplements in sports nutrition. The International Society of Sports Nutrition’s position stand concludes it reliably improves strength and power output when combined with resistance training, typically at around 3-5 g a day. Widely considered safe for healthy adults at these doses.
Whey or plant protein powder
Not magic, just a convenient, concentrated protein source. Genuinely useful if hitting your protein target from Lesson 4 through whole food alone is impractical on a given day. Whole food remains the priority whenever it is realistic.
Moderate evidence, situational
- Caffeine: reasonably strong evidence for improved alertness and exercise performance. Its effect on metabolism, mentioned briefly in Lesson 14, is real but minor, nowhere near enough to offset food choices on its own.
- Vitamin D: genuinely helpful for people who are actually deficient, which is common in Ireland and the UK given limited sun exposure for much of the year. Worth discussing with a doctor rather than guessing, since a blood test confirms whether it is actually needed.
- Omega-3 (fish oil): modest evidence for people who do not regularly eat oily fish. Prioritising the fatty fish covered in Lesson 6 is generally the better first move.
Weak or no credible evidence
“Fat burners”, CLA, garcinia cambogia, raspberry ketones, and most “detox” teas fall into this category. Independent reviews consistently find little to no meaningful effect on fat loss beyond what a placebo produces. Some fat-burner products have also been found to contain undeclared stimulants, which carries real safety risk, particularly for anyone with a heart condition or taking other medication.
If a product promises fast, effortless fat loss without addressing food or activity, that claim itself is the biggest red flag.
Today’s task
If you currently take a supplement, check which category from this lesson it falls into. If you are unsure, that uncertainty itself is worth a quick conversation with a pharmacist or doctor.
Check in with yourself
- Have you ever bought a supplement based on marketing rather than evidence?
- Is there a well-supported one from this lesson, like protein powder, that might actually be useful for you?
- Any new takeaway from today’s lesson you want to remember?
This lesson is general information, not a recommendation to take any specific supplement. Speak to your doctor or pharmacist before starting any supplement, especially alongside existing medication or a health condition.