Fish oil: tips and tricks


We often include fish oil in our therapeutic formulations, given that it is a rich source of the omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Unfortunately though, fish oil can be a bit tricky to handle sometimes; here's some tips and tricks:


Firstly, why can't I just use bottled fish oil instead of these annoying capsules?


Good question! I completely agree that capsules are not as easy to use, however I believe it's worth the effort. Bottled fish oil is exposed to a lot more oxygen, which means that it can become rancid (oxidise) a lot faster than encapsulated fish oil. Unfortunately, omega-3 fatty acids are highly prone to oxidation during storage, forming a complex mix of lipid peroxides, secondary oxidation products, and diminishing concentrations of unoxidised fatty acids.

Rancid fish oil smells and tastes horrible; much more concerning is that it is likely to have a range of detrimental health effects. More research is needed, however animal studies show that oxidised lipids may cause organ damage, inflammation, carcinogenesis, and atherosclerosis.


To minimise oxidation, we recommend storing both capsules and liquid fish oil in the fridge (this is essential for liquid products), and also making sure that the oil is not exposed to too much heat or natural light. Keeping fish oil products in the fridge also helps to minimise their odour and flavour a bit, which is an additional bonus. Purchasing fish oil from manufacturers that conduct careful testing to ensure the oil isn't oxidised prior to sale is also very wise; more on this further on.


My pet won't swallow these giant capsules - what should I do?


Not everyone is blessed with a ravenous Labrador who thinks that fish oil capsules are just another awesome snack. Most dogs or cats won't swallow these whole, even when mixed into a meal, or covered with something tasty like vegemite or peanut butter.


If you are feeling brave, you can just cut open the capsules with sharp scissors; be warned, this is a messy process and the fish oil can go everywhere, including on your hands! You only need to spill fish oil on your hands once to know that it's really not fun - even washing your hands multiple times doesn't remove the fishy stench. You can wear disposable gloves, or you can try out this quick and easy method:


1) Place required number of fish oil capsules in a small ceramic bowl.



2) Add a small amount of very hot water to the bowl - just enough to half cover the capsules.



3) Use a fork or spoon to stir the capsules and gently squash them. The oil will be released as the capsule shells start to soften and dissolve, forming a mix of warm water and fish oil.



4) Stir for another minute or so, and ensure that all oil has been released from the capsule shells.



5) Remove the softened capsule shells from the mix, and add the oil/water mix to your dog's meal. If using this method for cats, use as little water as possible.



You can sometimes use this method and just add the capsules to a hot meal, instead of water, and they will soften enough to release the oil and mix into the food - generally this works better with 'soft gels' rather than the firmer capsules.


What fish oil should I buy? There are so many choices!


We include specific brand recommendations in our consultations, however generally-speaking, I like to look for products that are MSC-certified (Marine Stewardship Council) and also IFOS-certified (International Fish Oil Standards™). These certifications are typically displayed on the product packaging, for example:













You can see the blue 'MSC tick' and the IFOS 5-star certified labels at the bottom of this excellent quality (and value) Nutrigold fish oil product.












Nordic Naturals is a very popular brand; they perform their own testing, so this is also a high quality option. You can even enter the lot number found on your bottle of capsules, and look at the certificate of analysis for that particular batch. We also like and routinely use products by Wiley's Finest, Carlson Labs, and Igennus, along with some more economical, local options for Australian and NZ clients.


What about flavouring added to the oils? Are human supplements safe for pets?


This is another good question. Many human fish oil products do have lemon or orange flavouring added to the oil, which can make these products a terrible choice for cats, since most cats have an aversion to citrus. Dogs with a good appetite may not mind this, so if your dog will eat anything, you can use these products without concern.

For fussier dogs and cats, it's better to us an unflavoured product, which can limit options to either a pet-specific product, or unflavoured human products. Some human products, like many Swisse fish oil capsules, actually have the flavouring in the capsule shell itself, rather than in the oil - so if you can remove the oil from the capsules, it's fine to use.

Otherwise, you can use a pet-specific product, such as Nordic Naturals Omega-3 pet fish oil (USA/Asia), Paw Blackmores fish oil 500: veterinary strength (Australia), Salpet Tasmanian salmon oil (Australia), or Omega Plus King Salmon oil (NZ):





Again, we don't routinely recommend pet-specific fish oil products because (a) they are generally bottled, and (b) they are often much less concentrated than human products. However, for some pets and owners they are the best option.

Human krill oil, salmon oil and calamari oil are often not flavoured either, so these can sometimes be a good choice as well.

Often it can be good to just try a few different products and experiment a bit, to see what works best for your pet. This is particularly the case for cats, as it can be a real challenge to persuade them to accept fish oil added to their meals.




If you would like more information on fish oil, or have any questions, please do get in touch: admin@vetnutritiongroup.com

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