WPI 90

These are the questions our naturopaths ask in store about isolate, starting with the main reason to choose it.

A good fit if

• Bigger amounts of dairy don't sit well, but a coffee or a yoghurt is fine. Less lactose is the main reason to choose isolate
• You count carbs or fat per serve closely enough that one or two grams makes a difference
• You want the shortest ingredient list you can get in a dairy protein, and an unflavoured isolate is about as short as it gets
• Thick, creamy shakes put you off, and a thinner or clear isolate is what you'd actually finish
• You've weighed up the grades and decided isolate gives you something you want

Check with us first if

• You're lactose intolerant. Isolate is low in lactose, not lactose-free, and no whey grade is certified lactose-free. Everyone's limit is different, and healthdirect notes most people can manage about half a cup of milk at a time.
• You have irritable bowel symptoms. With most of the lactose gone, the likely triggers in a flavoured isolate are the gums, sweeteners and sugar alcohols, so an unflavoured powder is the simpler one to try.
• You have, or have had, kidney or liver disease. How much protein you should have in total is a medical decision for your doctor.
• You have a soy or egg allergy. Isolate powders often contain soy lecithin to help them mix, and some list egg, so read the allergen statement rather than assuming a dairy powder only contains dairy.
• You're tested under an anti-doping code. Check the batch-testing status of any whey powder before you use it.
• You're buying from an overseas website. Those products aren't regulated in Australia for quality or safety.
• You take prescription medicines. Check with your doctor, pharmacist or our naturopaths before starting.

• Cross-flow microfiltered isolate (CFM, microfiltered, cold-filtered). Best known for: The membrane method. It separates by molecule size, so the whey proteins come through in close to their original proportions. Absorption: It doesn't need extreme heat or pH, which is why these powders are described as 'undenatured'. Typical use: The most common isolate on Australian shelves, and the default unless a label says otherwise.
• Ion-exchange isolate. Best known for: The chromatography method. It separates by electrical charge, using a resin that grabs proteins at a set pH and then releases them. Absorption: The whey proteins don't all carry the same charge, so this method recovers some fractions more easily than others and the protein mix isn't identical to the starting whey. Typical use: Less common in retail sports powders and rarely named on the front of a tub. If the label doesn't say, only the ingredient supplier's specification will tell you.
• Unflavoured isolate ('WPI 90' style). Best known for: Nothing is added after filtering, so the powder in the bag is close to the ingredient specification itself. Absorption: Mixes thin and can taste faintly of milk. Nothing masks it, which some people find plainer and others find harder to drink. Typical use: The simplest way to buy isolate, and the easiest label to check, because there's almost nothing on it.
• Flavoured isolate. Best known for: The mainstream format: isolate plus cocoa or flavours, sweeteners, salt and usually a gum or lecithin to help it mix. Absorption: The added ingredients dilute the powder, so the tub as sold sits below the 90 per cent figure even though the isolate inside it doesn't. Typical use: Everyday use. Check the protein per serve rather than the grade on the front, because they answer different questions.
• Clear whey isolate (juice-style). Best known for: Isolate treated so it stays clear in water and drinks like a cordial rather than a milkshake. Absorption: The same protein, presented differently. Serves are often smaller, so protein per serve is usually lower than a standard isolate scoop. Typical use: If you can't face a creamy shake, and for warm weather or after a session.
• Hydrolysed whey protein isolate. Best known for: Isolate partly broken into shorter peptides by enzymes after filtering, or isolate blended with a hydrolysate. Absorption: Faster again than plain isolate, and noticeably bitter, which is why it's usually blended rather than sold on its own. Typical use: A step up from isolate for a difference that hasn't been shown to change results. Worth trying only after you've tried a plain isolate.

Reference values. None. Whey protein isolate is a protein made from milk rather than an essential nutrient, so the NHMRC doesn't set a Nutrient Reference Value for it. You'll find Australia's protein reference values, and how much protein a serve should give you, on our protein powder and whey protein pages. This page is about what choosing isolate changes.

Typical supplemental range. The number in a name like 'WPI 90' refers to the raw ingredient measured dry, not to the flavoured tub in your hand. Once cocoa, sweeteners, salt and a thickener are added, the finished powder has less protein per 100 g. That's why two products can both be genuine isolates and list different amounts. Australian isolate labels usually list 24 to 28 g of protein in a 30 to 35 g serve.

Upper level. There's no Upper Level of Intake. With the lactose filtered out, what usually limits a single serve is the flavourings, not the protein. Sugar alcohols, gums and sweeteners are what most people notice first at two or three scoops.

Worth knowing. To compare products fairly, look at the grams of protein per serve on the nutrition panel, not the size of the tub. What you need depends on your age, diet and health, so talk to one of our naturopaths.

If any of these sound like you, talk to one of our naturopaths or your doctor before you start.

• Cow's milk protein allergy. Isolate is a milk protein, and removing lactose doesn't change that. It isn't suitable for you.
• Lactose intolerance. Isolate is low-lactose but isn't a certified lactose-free product, and everyone's tolerance is different.
• Soy or egg allergy. Soy lecithin is a common emulsifier in isolate powders and some products declare egg, so read the allergen statement.
• Kidney or liver disease, now or in the past. Talk to your doctor about your total protein intake first.
• Pregnancy. A product labelled as a formulated supplementary sports food must state that it isn't suitable for pregnant women except under medical or dietetic supervision.
• Children and teenagers under 15. The same required statement applies to formulated supplementary sports foods.
• Irritable bowel symptoms. Even with lactose removed, the gums, sweeteners and sugar alcohols in flavoured isolates are common triggers.
• Competitive athletes under an anti-doping code. Check for batch testing before you use it.
• Products bought from overseas websites. They aren't regulated in Australia for quality or safety.
• If you take prescription medicines, check with your doctor, pharmacist or our naturopaths before you start.