The supplement industry has made keto into a commercial opportunity. There is now a product for every stage of keto — keto-start capsules, exogenous ketone drinks, MCT oil in seventeen formats, electrolyte powders in forty flavours, and various combinations thereof. Most of it is not necessary. A few things genuinely help. Here’s the honest breakdown.
What’s actually useful
Magnesium is the one supplement that’s hard to argue against for people on keto. Most people are already deficient in magnesium on a normal diet; keto increases the rate at which your body excretes electrolytes, making the deficiency more pronounced. Symptoms include muscle cramps — particularly leg cramps at night — poor sleep, and the general fatigue associated with keto flu. Magnesium glycinate or magnesium citrate are the most bioavailable forms. Magnesium oxide is cheaper but absorbed less well.
In Belgium, magnesium supplements are available at any pharmacy without prescription. You don’t need a specialist supplement shop. The pharmacy own-brand versions at ING Pharma or Multipharma are perfectly adequate and cost a fraction of the branded versions in health food shops. Around €10-15 for a month’s supply. This is one purchase that’s worth making.
Electrolyte powder — a combination of sodium, potassium, and magnesium — is useful in the first few weeks of keto when the body is shedding water and electrolytes rapidly. Drinking salted water works but tastes bad. A basic unflavoured electrolyte powder mixed into water is more practical. These are not widely available in Belgian pharmacies or supermarkets; ordering from Amazon.de or a Belgian supplement retailer online is the most reliable approach. You don’t need this indefinitely — the acute electrolyte situation settles down after the first month.
What’s overhyped
MCT oil — medium-chain triglyceride oil derived from coconut oil — is frequently marketed as a keto essential. The actual evidence for it is modest: it converts to ketones slightly faster than regular fat, and some people find it useful for energy before exercise. For most people doing keto in a normal context, it’s an expensive addition that doesn’t change much. Available at some Belgian health food shops and online, costs significantly more than just eating butter or olive oil, and gives many people digestive issues at first. Probably not worth it.
Exogenous ketones — powdered ketone supplements that claim to raise blood ketone levels — are the most aggressively marketed and least worth buying. They’re expensive, the ketone elevation they produce is temporary, and there’s no good evidence that taking them improves anything in healthy people following a ketogenic diet. Skip them entirely.
Where to buy in Belgium
For magnesium: any Belgian pharmacy. Don’t pay health food shop prices for something your pharmacist stocks cheaply.
For electrolyte products: online is more reliable. Ketorade, LMNT (available on Amazon.de), or basic sports electrolyte products without sugar work fine.
For anything else: the Rob Bio sections, Färm shops in Brussels, or online. Don’t feel obliged to buy any of it just because someone on a keto forum said it was essential. The magnesium is genuinely useful. The rest is optional at best.
The supplement aisle at most Belgian health food shops will have products with “keto” on the label selling for significant money. The ingredient list usually reveals nothing special. The magnesium at the pharmacy down the street costs less and works better.