The bioavailability of a nutrient is the amount that is absorbed and utilized by your body. Foods contain a fairly consistent amount of nutrients, but their bioavailability varies depending on the preparation and cooking method.
You might think that the way to get the most nutrients from your food is by eating raw foods. But that isn’t always true. While some nutrients in certain foods are best absorbed when eating them raw, others are actually more bioavailable after cooking, mashing, cutting, soaking or when eaten in combination with other nutrients.
Today you’ll learn six ways to get the most out of your bone-healthy pH-balanced diet so you can be sure that you’ll get the maximum benefits from the nutrients in the foods you eat.
1. Store Your Foods To Preserve Their Nutrients
Two big storage mistakes that can lead to wasted nutrients. The first is storing foods in a way that prevents you from actually eating them. This sounds obvious, but if you always place your carrots in the bottom of your vegetable drawer in the refrigerator, then you might forget about them, causing your storage system to thwart your nutritional goals.
The second mistake is storing fruits and vegetables in places that lead to the degradation of nutrients. Generally speaking, heat, light, and oxygen all take a toll on nutritional content. Your fruit basket might look pretty hanging in the window, but the sun can sap your foods of the vitamins your body and your bones need.
Here are some additional guidelines for storing your produce:
- Store herbs in the freezer-chopped and frozen in water or oil using an ice cube tray or a zipper-lock bag.
- Vegetables should go in the refrigerator (except for root vegetables, which you can keep at room temperature).
- Fruits, with the exception of berries, should be stored at room temperature and away from direct light. This includes tomatoes and avocados. If you’ve been keeping them in the fridge, you’ll be amazed at how much more flavorful they are unrefrigerated.
- For cut fruits and veggies, a squeeze of lemon juice will slow oxidation- then store them in an airtight container.
Store foods where you’ll remember to eat them, away from heat and light. Vegetables (except root vegetables) go in the refrigerator, and most fruits (except berries) should stay at room temperature.
2. Combine Foods For Maximum Nutrient Absorption
Combining different foods is more than just a matter of taste, it actually changes how well we absorb nutrients. Here are three rules of thumb to help you get the most out of your meals:
1. Plant Sources Of Iron Are Best Absorbed Alongside Vitamin C
The iron in plant-foods becomes more readily available when paired with foods rich in Vitamin C. The vitamin both helps the iron to be absorbable and blocks other compounds that can inhibit absorption.
Vegetarian sources of iron include:
Vitamin C-rich pairings include:
- Freshly squeezed lemon juice*
- Bell Peppers*
- Chili Peppers*
- Spinach* (Amazingly, spinach contains both nutrients!)
- Brussels Sprouts*
* Denotes Foundation Foods
2. Pair Fat-Soluble Vitamins With Healthy Fats
The fat-soluble Vitamins A, D, E and K are most bioavailable when eaten with dietary fats. This allows the vitamins to dissolve into the fats, making them easier for your body to absorb.
Here are some examples of foods rich in each of these vitamins:
- Vitamin E: Avocado*, Swiss Chard*, Spinach*, Asparagus*, Mango
- Vitamin A: Carrots*, Squash, Sweet Potatoes*, Red Pepper, Mango
- Vitamin K: Spinach*, Brussels Sprouts*, Broccoli*, Kale*, Asparagus*, Green Peas*
- Vitamin D: Mushrooms*, Eggs*
* denotes Foundation Foods
When these foods are on your plate, consider including a small portion of a food containing a healthy fat, like some nuts, avocado, or olive oil.
Some foods have the remarkable quality of containing both fat-soluble vitamins and the fat required to dissolve them. That’s a good reason to include foods like salmon, sunflower seeds, herring, and almonds. Just be sure to balance acidifying foods (like salmon and herring) with alkalizing ingredients, using the 80/20 acid/alkaline ratio.
3. Pair Iron-Rich Animal-Products With Sulfur
While the guidelines of a pH balanced diet favor plant-based foods, the nutritional guidance in the Osteoporosis Reversal Program is not about forbidding particular foods- it’s about achieving a balance that builds stronger bones and improves overall health.
Based on that, when you eat acidifying animal products, it makes good sense to get the most out of them. Foods rich in iron (like liver or beef) or zinc (like turkey or oysters) are best consumed alongside foods that contain sulfur.
Pair those foods with sulfur-rich cruciferous vegetables (such as broccoli, cauliflower, cabbage, and Brussels Sprouts), and with garlic or onions, so that the sulfur they contain will bind with the minerals in the meat, helping you to absorb them. It turns out liver and onions is a classic dish for a good reason!
Consume plant sources of iron with Vitamin C and animal sources of iron with sulfur. Eat fat- soluble vitamins (A, D, E, and K) with small amounts of healthy fats such as olive oil.
3. Eat These Foods Raw To Absorb Their Water-Soluble And Heat-Sensitive Nutrients
Heat breaks down Vitamins B1, B5, B9 (folate), and C. When you cook foods that are rich in these vitamins, you actually reduce their levels.
To get these vitamins, try eating foods raw or cooking them at low heat. Because they’re water-soluble, cooking in water does them double the damage- the vitamins are degraded by the heat, and they dissolve in the water, containing a shadow of their former nutrient content.
Here are some examples of foods best eaten raw to get the most of these water-soluble vitamins:
- Vitamin C: Bell Peppers*, Brussels Sprouts*, Broccoli*
- Vitamin B5: Broccoli*, Kale*, Avocado*, Cauliflower*
- Vitamin B9: (Folate): Spinach*, Turnip Greens, Broccoli*
- Vitamin B1: (Thiamine) Green Peas*, Beet Greens, Brussels Sprouts*, Sunflower Seeds*
* Denotes Foundation Foods
Studies have shown that including raw foods in your diet has positive effects on your cardiovascular health. But the same line of research found that diets consisting of entirely raw-foods can lead to critical nutritional deficiencies, including bone loss.1
Steaming or blanching is a reasonable middle ground if your dish won’t allow for a raw option, but remember that boiling undoes many of the health benefits of these foods (and doesn’t do much for their flavor either!)
Eating raw fruits and veggies protects certain vitamins from degradation – especially Vitamins C, B1, B5, B9. Diets rich in raw foods are also beneficial for cardiovascular health.
4. Prepare Your Foods To Release Their Power
Certain forms of food preparation can make their nutrients more bioavailable.
- Slice and dice your fruits and vegetables to break down the plant cell ways, unleashing the nutrients within, and making them easier for your body to absorb
- Crush or chop garlic and onion to release an enzyme called alliinase that forms an immune boosting nutrient called allicin.
- In reference to soaking grains and beans to reduce phytic acid, please click here to read an article that explains its effect on bone health and overall health.
Slice and dice fruits and vegetables to unlock their nutrients. Crush or chop garlic and onions to release immune-boosting nutrients.
5. Shop Local
Produce is more nutritious when they’re recently harvested. After the harvest, most fruits and vegetables rapidly start to lose their nutritional density.2 That means the farmer’s market (or your backyard garden!) is the best way to access maximum nutrient content.
Don’t get too hung up on this idea, however. You’re better off eating a wide variety of plant- based foods from grocery stores, or shipped from other states, than eating the same thing over and over just because it’s available locally. But if you have a choice between ingredients that are freshly harvested and ones that aren’t, know that the fresher option is also more nutritionally dense.
Fruits and vegetables start losing nutrients after they’re harvested, so eat them as soon as possible, and buy them as fresh as possible.
6. Know The Effects Of Cooking
Cooking changes your food. That much is obvious, but exactly how it changes nutrients, antioxidants and other compounds is a complicated matter.
A safe rule of thumb is that higher heat and more water mean fewer nutrients. That said, there are certain exceptions. For example, one study found that boiling actually increased the antioxidant levels of carrots.3
Here are some facts about the impact of different cooking methods:
Frying And Sauteing
- No mineral leaching due to water
- Heat can degrade B and C vitamins
- The added oil improves absorption of oil-soluble vitamins
- Low cooking time reduces heat-destruction of nutrients
- Some unsaturated fatty acids and antioxidant vitamins are lost due to oxidation4
- One study found french fries maintained their Vitamin C content4
- Frying/Sauteing at home is healthier than commercial deep frying
Roasting And Baking
- No added water to leach minerals
- Some nutrient loss from heat
- Studies have shown roasting can preserve B Vitamins better than frying5
- Allows moderate use of healthy oils to improve fat-soluble vitamin absorption
- Extremely gentle
- Steam doesn’t leach minerals like boiling
- One study found that steaming maintained Vitamin C content in broccoli6
- That study found that steamed broccoli had higher antioxidant levels
- Increases beta-carotene, lutein, and alpha- and gamma-tocopherols in broccoli6
- The heat breaks down Vitamins B1, B5, B9 and C
- The water leaches vitamins and minerals alike
- Reduces polyphenols
- Consuming the water (as with a soup) means you don’t lose leached nutrients
- Reduces goitrogens, which are compounds that may exacerbate existing thyroid problems
- Study found boiling increases beta-carotene, lutein, and alpha- and gamma-tocopherols in broccoli6
- Fast cooking times are easy on nutrient content
- One study found microwaving peppers did not reduce their polyphenol or Vitamin C content7
- Another study found that turnip greens maintained more B and C vitamins when microwaved instead of blanched in boiling water8
- Microwaving is a controversial form of cooking, so we will soon devote an entire article to this topic
Certain foods contain compounds that increase their bioavailability when cooked. Tomatoes, for example, contain a bone-protective antioxidant called lycopene that’s made more bioavailable when the tomato is cooked with olive oil.9
The example of broccoli illustrates the nutritional choices that cooking provides. Eating raw broccoli ensures you get the maximum amount of B Vitamins, but steaming actually increases antioxidant levels, and boiling or steaming increases beta-carotene levels. You can toss it raw into a salad to access certain nutrients, and steam it for a side dish to get others.
Use a variety of types of food preparation to unlock the benefits that different cooking methods offer. Boiling tends to sap the most nutrients from foods, while steaming is relatively low impact and may increase certain healthy compounds.
How You Prepare Foods Makes A Difference!
Don’t think like these variations mean there’s a right and a wrong way to prepare your foods. Instead, celebrate that you have options that provide many ways to access bone-smart nutrients.
Eat Your Way to Stronger Bones!
Discover over 200 mouth-watering bone healthy recipes for breakfast, smoothies, appetizers, soups, salads, vegetarian dishes, fish, and plenty of main courses and even desserts!
Eating a variety of foods prepared in different ways will support a well-rounded, balanced diet that provides the nutrients your bones and your body need to stay healthy.
Till next time,
1 Koebnick, Corinna, et al. “Long-Term Consumption of a Raw Food Diet Is Associated with Favorable Serum LDL Cholesterol and Triglycerides but Also with Elevated Plasma Homocysteine and Low Serum HDL Cholesterol in Humans.” J. Nutr. 135. 10. (2005): 2372-2378. Web. http://jn.nutrition.org/content/135/10/2372.long
2 Barrett, D. M. “Maximizing the nutritional value of fruits &
vegetables.” Food Technol. 2007, 61, 40−44. Web. http://www.fruitandvegetable.ucdavis.edu/files/197179.pdf
3 Cristiana Miglio, et al. “Effects of Different Cooking Methods on Nutritional and Physicochemical Characteristics of Selected Vegetables.” J. Agric. Food Chem., 2008, 56 (1), pp 139–147. Web. https://pubs.acs.org/doi/full/10.1021/jf072304b
4 Fillion L., et al. “Nutrient losses and gains during frying: a review.” Int J Food Sci Nutr. 1998 Mar;49(2):157-68. Web. https://www.ncbi.nlm.nih.gov/pubmed/?term=Nutrient+losses+and+gains+during+frying%3A+a+review.
5 Zhao H., et al. “Study on vitamin B1, vitamin B2 retention factors in vegetables.” Wei Sheng Yan Jiu. 2008 Jan;37(1):92-6. Web. https://www.ncbi.nlm.nih.gov/pubmed/18421876
6 Gliszczyńska-Swigło A. et al. “Changes in the content of health-promoting compounds and antioxidant activity of broccoli after domestic processing.” Food Addit Contam. 2006 Nov;23(11):1088-98. Web. https://www.ncbi.nlm.nih.gov/pubmed/17071511?dopt=Abstract
7 Ai MeyChuah, et al. “Effect of cooking on the antioxidant properties of coloured peppers.” Food Chemistry. Volume 111, Issue 1, 1 November 2008, Pages 20-28. Web. https://www.sciencedirect.com/science/article/pii/S0308814608003191
8 M. A. Osinboyejo, et al. “Effects of microwave blanching vs. boiling water blanching on retention of selected water-soluble vitamins in turnip greens using HPLC.” Presentation.
Institute of Food Technologists Annual Meeting, Chicago, IL, July 15, 2003. Web.
9 Fielding JM et al., “Increases in plasma lycopene concentration after consumption of tomatoes cooked with olive oil.” Asia Pacific Journal of Clinical Nutrition. 2005. Web. https://www.ncbi.nlm.nih.gov/pubmed/15927929