Most of the produce you buy in a grocery store does not have anything close to the mineral profile it is supposed to have according to nutritional textbooks. This is because minerals are not manufactured by plants, whereas vitamins and phytonutrients are. When plants create such nutrients, they synthesize them through chemical and energetic processes that can only be called miraculous. But as capable as they are, plants do not create minerals. Minerals have to be absorbed through the soil, and if they are not present in the soil, then the plant's roots cannot take them up, and therefore they will not be present in the plant.
The nutritional and mineral profile of the plant ultimately depends on the mineral content of the soil. Since soils today are so over-farmed and depleted of all but a few basic minerals, most of our produce lacks the minerals they should contain. For example, a lot of plants absorb selenium when selenium is present in the soil. But when selenium is not present in the soil, of course it's not available to the plant. The plant gets grown and taken to the store and sold and consumed anyway, even though it doesn't have the levels of selenium that it should contain according to traditional textbooks.
Interestingly, tomatoes can be grown to look very good cosmetically, even though they lack selenium and all the minerals that should be present. It really only takes three minerals to grow tomatoes or other vegetables. Of course, those vegetables will be nutritionally deficient, which means they won't be as healthy as they could be. They won't be as resistant to disease and pests, and they won't taste nearly as good either. So if you are eating tomatoes or produce grown in nutritionally depleted soils, then you are consuming inferior produce, and that's what's available in stores today.
Here's a common question about minerals and produce: How do tomatoes or other plants know which minerals to absorb? The answer is that each plant has a different mineral absorption profile. A tomato will absorb a certain number of minerals (around 56), and it will absorb no more. It will only absorb the 56 that it is programmed to absorb.
Grasses for example, will absorb over 70 minerals. Sweet potatoes, or yams, absorb more minerals than potatoes, and some plants absorb fewer minerals. Some plants absorb only 20 or 30 minerals. Each plant has a different profile of what it will absorb. Of course, it can only absorb what is present in the soil. So even though a tomato should contain 56 minerals, you may be eating a tomato purchased at the grocery store that only contains 12 minerals or 7 minerals. You are missing out on all the minerals it could have.
This is why it's a great idea to eat Brazil nuts from time to time, because Brazil nuts are the only commonly available nut that's grown wild in naturally mineralized soils. Brazil nuts are mostly wild crafted, meaning that they are collected out in nature from wild plants, and they are very high in selenium. In fact, just eating three Brazil nuts a day gives you the minimum daily requirement for selenium. Of course, selenium is a very important mineral for preventing Alzheimer's disease, preventing cancer and many other disorders. It's also a great anti-viral mineral.
The point of this is that, when we read in a book that Kale is a great source of calcium, or that broccoli is a good source of selenium, we really have to imagine an asterisk behind that statement. Kale may be a good source of calcium if there was calcium present in the soil in which it was grown. Broccoli may be a good source of selenium, but only if selenium was present in the soil.
Following the late 2004 tsunami in Thailand, the soils there produced outstanding crop yields because ocean water had been deposited onto the land. Ocean water contains all the minerals we need, and those minerals helped create an abundance of crops in the following season.
Back at the dawn of human civilization when we lived along the Nile, the river regularly flooded and would bring nutrients and minerals back to the croplands. That is what sustained early human civilization. The dawn of agriculture was dependent on the flooding of a river. Had that river not flooded and that land been farmed over and over again from generation to generation, the civilization there would have died due to malnutrition. It could not have sustained itself.
Much the same is happening in the United States today. Our civilization is crumbling for a number of reasons related to health. Our population is more diseased than any population in recorded history. Our mental capacity is diminished more than any other population. We have health care costs that are bankrupting our corporations and bankrupting our economy. We are on the verge of a collapse in part caused by a lack of mineralization. It sounds simplistic, but it's absolutely true. Health is the foundation of all abundant civilizations. Without health, there can be no trade, education, peace or abundance. Without mineralization, there can be no health.
The next time you go shopping for produce, don't trust the mineral claims on fruits and vegetables, nuts and seeds. If you want to boost the mineral content of the foods you buy, buy organic. Organic foods almost always have higher mineral concentrations than conventionally grown foods.
If you really want to do it right, grow your own food and apply diluted seawater (or trace minerals water) to your soil. That will give you the healthiest, highest mineral density plants available anywhere in the world. You can only grow them yourself because I'm not aware of any commercially grower using seawater, which is a great oversight. The source I recommend for seawater is called OceanGrown.com. They will sell you concentrated seawater that you can then dilute and apply to your garden.