Time to start thinking about the seasonal nutrition in fresh foods that we eat as we go into winter in the southern hemisphere. Heading in to autumn may seem like a time when some fresh foods like mangoes disappear. But more and more foods seem to be available for longer and longer, if not all year around, like strawberries. This might be convenient, but it isn't always the healthiest option.
There is always a fruit for the season and right now in Australia it is pumpkins
Our favorite science reporter loves to cook, and Jonica's Pumpkin Seaweed Pasta recipe is to die for. A double whammy of fibre and anti-oxidants like lutein.
Pigments like lutein are an anti-oxidant and used to protect us against light oxidative damage. This is important on our skin, but of course also in our eyes. It is here that lutein plays a big role in food as it helps to reduce the risk of macular degeneration, especially from blue light exposure.
However because lutein is light sensitive and takes the hit of oxidation instead of your eyes, you want to protect lutein from light before you eat it! Otherwise it isn’t doing anything. This is where foods like our seaweed and pumpkin can be dried, cooked and still give you lutein, as long as you keep them out of storage in light. Keep them in a pantry cupboard or a darker spot. The best way to eat them though is in season to get the freshest source of lutein. Lucky our seaweed grows all year round through, even if pumpkins don't, heh!
Preserving food has been important throughout history
We can dry, ferment or freeze many foods and keep many important health properties of foods intact. These are ancient processes for nutritional availability throughout the year. But modern methods of long term storage or sterilisation of foods to keep them available as a fresh food is less desirable.
Fresh foods should be seasonal
The best way to eat fresh food is to follow the seasonal pattern for three important reasons:
- Active phytochemicals, like vitamins, die off in long term, chilled, wet storage and irradiation
- Healthy microbes for a healthy gut microbiome get killed during irradiation for longer shelf life
- Sometimes less desirable chemicals, a.k.a. preservatives, are used to reduce spoilage and we still don’t know enough about most chemicals and how they affect us or our microbiota
How out of season fresh foods get to us
Foods that are available out of season are either transporting loads of water rich foods for miles over the planet in chilled storage, and when this happens they are also often irradiated to effectively sterilise them for reasons of biosecurity and spoilage. You might not be aware of the radiated food symbol – but look out for it on your blueberries, raspberries and strawberries, among other foods. Imported strawberries are nearly always irradiated, and the Queensland Government is looking to increase irradiated foods.
Don't confuse safe with healthy
Irradiated foods are not unsafe to eat, so you should not feel concerned if you need that punnet of strawberries for a desert tonight and there are only irradiated strawberries available. As a general rule though, if we keep choosing long-term cold storage and irradiated foods, we are losing a lot of the diversity of nutrition and health that fresh food offers. Irradiation is done to kill bacteria and pathogens, but it is also killing a source of important probiotics form healthy plants with healthy microbes. A bit like an antibiotic dose in our guts – it kills everything and even the good microbes.
Some treatments are probably not safe
Chemically treated foods for shelf life are more commonly known as preservatives. These might not only be unhealthy for us, but they also affect the microbes on our food and in our guts. Some studies showing that inflammatory bacteria can be promoted while anti-inflammatory promoting bacteria can be depleted in some cases of preservative use. The best way for ward is to avoid poorly understood and modern preservatives; but we should all know this message by now. There are natural preservatives, however, that we have used for millennia, including salt and some herbs like rosemary.
Fresh foods are a source of probiotics
When we pick a lettuce in our garden, we should rinse off any dirt, but this doesn't kill off the healthy microbes on a healthy plant. Probiotic microbes are on all fresh foods and are a part of the starter culture for fermented foods like sauerkraut and even wines. Clean, healthy fresh plants make up a small supply of probiotic bacteria with the latest in probiotic activity for staying on top of a healthy gut.
This is why we should focus on clean fresh foods, not sterile, long storage fresh foods. A washed, fresh strawberry in spring is going to deliver much more diverse plant and gut nutrition compared to long term storage, irradiated and sterile strawberry. Glass houses can help in making strawberries available for a longer time of year but keeping things warmer and lighter, but we should still respect the seasonality that still limits fresh food production.
Nutrition year round comes from naturally preserved foods as well
A good way to preserve nutrition throughout the year when fresh food is less available is to make traditional conserves with fruits, fermented or pickled food in jars, salted foods like olives, as well as straight desiccation of pantry goods. These foods might lose some of the nutritional activity in drying, but in some cases like fermented foods, they also gain nutritional benefits. Also dried foods can still maintain sleepy gut healthy microbes, like Lactobacillus rhamnosus, that jump back into life to help inside a healthy gut. Micronutrients like iron and magnesium are also preserved to keep up important micronutrients throughout the year.
Dried seaweeds are known to be a great source of nutrition throughout the year, maintaining a source of trace minerals from the ocean year round as in PhycoSalt, dietary seafibres that bounce back into gut healthy gels when consumed, and even natural probiotic bacteria that are carried with your pantry seaweed products like bioavailable iron in PhycoMuesli.
Did you know that the the Maori battalion travelled to WWII carrying nori in their satchels!
Because they understood the essential nutrition that seaweed could provide in it's dried form.
As humans we have lived a long time with many traditional ways to preserve nutrition, and for me, these are still the best ways. We still don't know enough yet to understand the complexity of foods, nutrition and our gut ecology to put into place less validated methods such as irradiation, long term storage and chemicals for a majority of foods. Stay healthy with fresh seasonal, fermented, dried and pickled things in life, keeping them in cool, dark storage as needed.