Are you notorious for having the same, perfectly portioned, set lunch for work that you’ve meticulously packed for the whole week ahead? If you’re a meal prep junkie, you’re likely making a few common mistakes that could seriously be damaging the nutritional content of your food, and I’m going to tell you how to fix them! The Meal Prep Routine We all know why we meal prep – we’re busy, we’re rushed, we’re tired – all of these reasons and more make it inevitable that if you don’t plan ahead, you may end up scarfing down a fast food burger and two chocolate bars out of pure starvation and easy access. So, instead of putting ourselves in such a position, we grill our chicken and steam our veggies on a Sunday night and pack everything away into perfect little portions to get us through the week. But has it ever occurred to you that Friday’s chicken, rice and veg may actually be nutritionally different to when you ate it on Monday? It’s no secret that food doesn’t keep its nutritional contents forever, and unfortunately this means that by the end of the week your food might not be as nutritious as it once was, especially depending on your meal prep routine. Where Oh Where Have My Nutrients Gone!? So I’m sure you’re all wondering how could the exact same lunch be less nutritious, and where did the nutrition go? It can’t just disappear into thin air, can it? The obvious way to consider this is to think of food spoilage – you wouldn’t eat food left in your fridge for weeks or months, and you’d probably get sick if you did. But this spoilage doesn’t happen overnight, and there’s actually a load of awesome scientific reactions occurring in the shorter term that result in altered nutrient values. So let’s take a look at what’s going on: Oxidation Oxidation is a reaction that occurs when oxygen is able to access foods, and is often responsible for producing funky odors, flavours and colours1. Think of a sliced apple that turns brown – this is oxidation! Unfortunately, when foods oxidize, certain nutrients can lose their activity, and although this doesn’t necessarily mean the food is unsafe for consumption, it does mean that you may have lost a lot of the goodness that made your meal nutritious in the first place. Histamine levels Histamines are compounds most well-known for their involvement in inflammatory reactions. Think of someone you know who takes anti-histamines to control allergy symptoms. What most people don’t realize is that histamine also plays a role in several other disorders, with many people suffering with issues such as eczema, IBS, urticaria, and even fibromyalgia showing to possess histamine sensitivities. Studies have shown histamine content to increase in foods over time2,3, and consuming leftovers can actually make the difference between feeling fine and having mild or even symptomatic inflammatory reactions in some individuals. Microbial growths Microbes like food. Just as it does for us, food provides microbes with nutritional requirements necessary for growth and proliferation4,5,6. These microbes can be harmful themselves, or can participate in reactions that produce compounds which are unsafe for consumption. These factors begin proliferating before we can visibly notice and, if consumed, could contribute to negatively impacting your digestive processes by messing up the body’s natural bacterial balance, increasing your toxic load, or producing unwanted inflammatory responses. Nutrient degradation Nutrient degradation occurs over time, and is influenced by various factors, notably including the time and temperature of storage. Several studies have shown that heating storage methods influence nutrient contents including phytonutrients such as flavonoids and carotenoids, vitamins, minerals, etc.7,8,9 To exemplify this, just think of how much longer food stays fresh in the fridge. Luckily, this is one of the simplest factors for you to control. All of the processes above are naturally occurring, so are not easy to put to a complete stop. However, there are a few easy things you can do at home to slow down and minimize the negative impacts on your food. Meal Prepping to Optimize Nutritional Benefits In a perfect world, I would of course tell you the solution is to go pick fresh vegetables from your garden and make a home-grown summer salad while slow-cooking a salmon that you caught fresh from the river, but let’s get real. You’re busy, so I’m not going to take your meal prepping ways away from you. What you can and should be doing however, is using a few simple meal prep techniques which will retain nutrient content and reduce oxidation and the probability of harmful exposures. This will allow you to optimize the balance between juggling your jam-packed life, minimizing your kitchen commitments, and maximizing your overall health and fitness. How to Meal Prep Like a Pro Freeze Your Meals One of the best ways to cut corners while maximizing nutritional preservation is by preparing chopped, ready-to-cook raw meals and freezing them. Once you arrive home, throw your bagged stir-fry in a pan, or add your chicken and veggies to a slow-cooker before you head off for work, and by the time you’ve had a chance to change your clothes and wind down, dinner’s already ready. This technique is comprehensive enough to prevent microbial growths, oxidation and sharp histamine increases, while retaining way more nutrients than cooked and stored food. Invest In Good Storage Containers Investing in sturdy, air-tight containers can help to prevent oxidation and microbial growths, maintain the appearance and taste of your meal and, most importantly, protect your nutrients. Additionally, it’s important to consider that common food storage supplies, especially plastics and cling films, actually contain chemicals that can get absorbed by the foods you’re eating. Investing in high quality containers which are free of soluble chemicals (such as these) therefore also contributes to a strategy for reducing your body’s toxic load. Minimize Transport Stressors As discussed above, temperature storage has a significant impact on nutrient degradation. Keeping your meals stored at a consistent temperature during transport, especially if you have a long commute, can significantly preserve nutrient content. Easy ways to minimize transport stressors include investing in a small cooler bag or thermal lunch box. Reheat Appropriately It’s widely known that heating food destroys certain nutrients10,11,12 – and doing it multiple times at high temperatures can destroy even more. Try and ensure you’re sticking to reheating your food as minimally as possible, only once and not too hot, or even adding in the vegetables raw and heating them for the first time when you consume the meal. This will decrease thermal stressors to optimize nutrient preservation. So there you have it – 4 super simple ways to get more nutrition from eating the same food. How easy was that!? Try some of these tips for this week’s meal prep, and let me know how it goes in the comments below! Stay healthy, Anita Tee MSc Personalized Nutrition, BSc Genetic & Molecular Biology, Personal Training Specialist References 1. Löliger J. Headspace gas analysis of volatile hydrocarbons as a tool for the determination of the state of oxidation of foods stored in sealed containers. Journal of the Science of Food and Agriculture. 1990;52(1):119-128. 2. Rice S, Eitenmiller R, Koehler P. Biologically Active Amines in Food: A Review. Journal of Milk and Food Technology. 1976;5:322-375. 3. Bodmer S, Imark C, Kneubühl M. Biogenic amines in foods: Histamine and food processing. Inflamm res. 1999;48(6):296-300. 4. Remenant B, Jaffrès E, Dousset X, Pilet M, Zagorec M. Bacterial spoilers of food: Behavior, fitness and functional properties. Food Microbiology. 2015;45:45-53. 5. Doulgeraki ANychas G. Monitoring the succession of the biota grown on a selective medium for pseudomonads during storage of minced beef with molecular-based methods. Food Microbiology. 2013;34(1):62-69. 6. Zhao F, Zhou G, Ye K, Wang S, Xu X, Li C. Microbial changes in vacuum-packed chilled pork during storage. Meat Sci. 2015;100:145-49. 7. Hidalgo ABrandolini A. Kinetics of Carotenoids Degradation during the Storage of Einkorn ( Triticum monococcum L. ssp. monococcum ) and Bread Wheat ( Triticum aestivum L. ssp. aestivum ) Flours. J Agric Food Chem. 2008;56(23):11300-11305. 8. Achir N, Pénicaud C, Bechoff A, Boulanger R, Dornier M, Dhuique-Mayer C. 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