INSIDER spoke with several dietitians to find out what those foods are and how they can benefit you as you mature.
One of the most valuable sources of protein and nutrients that you can eat are eggs, according to Pamela Schoenfeld, MS RD LDN. They are rich in choline, biotin, and protein.
Protein protects you from bone and muscle loss, Schoenfeld explained, and supports immune function. Choline helps the liver clear fats, and biotin is needed for energy, skin, and nails.
If you buy eggs from pastured chickens, they contain vitamin K2, which works together with vitamin D and A to put calcium into the bones and keep it from depositing in the arteries. Plus, they contain even higher levels of lutein and zeaxanthin, Schoenfeld told INSIDER, which are potent antioxidants that protect the eyes especially from macular degeneration - an eye disease that leads to vision loss.
"Oysters are by far the best dietary source of zinc, which many people, especially those who limit red meat consumption, can fall short on," Schoenfeld told INSIDER.
Zinc supports your immune system, along with vitamin A, she explained, and it also helps support healthy hormone levels no matter your sex.
Another category of foods you'll want to incorporate into your diet are citrus fruits, Schoenfeld told INSIDER. Citrus should be eaten whole, preferably with the skin and, when organic, have a bit of the peel or zest too.
"Citrus is rich in vitamin C, the white netting around it is abundant in bioflavonoids which strengthen the blood vessels, and the peel is rich in limonene which is anticancer and anti-inflammatory," Schoenfeld said.
There is some evidence to support this, however, more research needs to be done in regards to limonene's anticancer properties.
"Fermented dairy is not only a superior source of beneficial bacteria for the gut and overall health, it supplies much-needed calcium, which not only is needed for bones, but it also keeps our blood in an ideal pH range," Schoenfeld said.
If you aren't consuming enough calcium, the body will draw calcium from your bones to keep the blood calcium in a normal range, she explained. You can consume fermented dairy in the form of kefir, yogurt, or cheese.
The cabbage family, also known as cruciferous vegetables, includes kale, broccoli, cabbage, brussels sprouts, cauliflower, and several others. These vegetables supply sulfur, a necessary nutrient for our skin, joints, and practically everything in the body, Schoenfeld said. Plus, they support our detoxification pathways, which allows the body to effectively remove toxins.
"Just make sure not to overdo it - two servings per day, about 1-2 cups, will take care of your needs. More than that may interfere with the body's use of thyroid hormones," she told INSIDER.
If you're looking for something simple to top off your meal, try adding turmeric, cinnamon, or rosemary for extra health benefits. "These are special in that they help reduce inflammation, support good blood sugar control, and protect and support cognitive function," Schoenfeld told INSIDER.
She also recommended mushroom extracts, sesame seeds, and black pepper to help with the absorption of nutrients from spices like turmeric.
Fatty fish in particular, such as salmon, tuna, and sardines, are a great source of high-quality protein, according to Stephanie Bostic, Ph.D., RD, and owner of Balance: Food and Nutrition.
Fish also provides valuable omega-three fatty acids that are associated with better mental health and decreased cognitive decline, she explained. Merely eating fish twice a week can allow you to start reaping some of these health benefits, Bostic added.
Beyond being a great snack, nuts are good for longevity, according to Bostic. "People who eat nuts tend to have improvements in useful blood values, like their cholesterol. Nuts are also a lovely source of fibre, protein, and healthful fats," Bostic told INSIDER.
As you age, many older adults are less able to absorb the B12 naturally found in foods, Bostic said. "Because they naturally begin to have a lower level of acid in their stomach or take medications that alter their stomach's environment, the process needed to digest and absorb B12 is impaired," she told INSIDER.
Therefore, eating food with added B12, such as B12 fortified cereal or milk, can help prevent a deficiency because synthetic B12 is more easily absorbed, Bostic explained.
Collagen protein keeps bones and joints strong, revitalises skin, and supports good detoxification and blood sugar management, according to Schoenfeld.
Poultry and fish skin, the bones from canned salmon, and bone-based broths and soups are great sources of collagen protein, she told INSIDER.
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