Not seeing the results you want at the gym? Any number of things could be causing your progress to stall, but protein missing from your diet might be to blame. "If you go to the gym, you could take longer to recover or don't see muscle gain after a workout. Low protein levels can cause muscle loss and wasting," Butler says. When you don't have enough protein, the proteins that would have otherwise been used for muscle building and repair are used to supply more vital tissues. When you break down your muscles during a workout, they may simply wear away instead of building up stronger during repair. Your body needs more protein to build your strength back up again. This protein doesn't have to come from a protein bar or shake; it can come from nutritious foods in your meals and snacks.
Your hair, skin, and nails feel brittle and dry
"Our skin, hair, and nails are made primarily from a protein called keratin, which requires protein from your diet to produce," registered dietitian Katey Davidson explains. If you don't have enough keratin in your system, your skin, hair, and nails will suffer. "Collagen is another important protein," Davidson says. "It relies heavily on the amino acids proline, glycine, and lysine for its production." Those amino acids come directly from eating certain protein-rich foods. That's part of why eating salmon, eggs, and Greek yogurt can actually give you better hair.
You're always getting sick
You may not realize it, but protein is a major fuel source for assuring the health of your immune system. "A decrease in protein can affect how efficiently your immune system works," says Butler. When your immune system falters, it can result in frequent illness, difficulty recovering from injury, and worse symptoms when you are sick. "Simply put," she says, "a common cold can last much longer."
Your arms or legs look puffy
This symptom only occurs in rare cases of severe protein deficiency, which mainly occurs in developing countries. But, Davidson says, "A very low protein diet could lead to fluid accumulation called edema. Eating a protein called albumin helps prevent fluid from accumulating in areas of the body." But, she notes, this is very rare.
You're experiencing intense food cravings
Food cravings are, for the most part, fairly normal. If you smell pizza in the oven, it makes sense that you crave a slice. But if the cravings seem random, intense, and distracting, it could be a sign that you're missing something from your diet. A food craving can, in some instances, be a signal from your body that it needs that food. "Lack of satisfaction or craving other foods after a meal could be a sign you need more protein," registered dietitian Melissa Giovanni told The Daily Meal. "We need adequate carbohydrate and protein throughout the day to make the neurotransmitters and hormones that provide satisfaction."
You're having trouble sleeping
Tryptophan, an amino acid found in proteins such as those found in turkey breast, is essential for the production of a hormone called serotonin. "You need adequate protein throughout the day to produce serotonin, which your body converts to melatonin at night," Giovanni explains. Melatonin is a hormone that regulates wakefulness and sleep. Without enough of it in your system, it may be difficult to fall asleep at night. "If you do not have enough serotonin to make enough melatonin, it may result in poor sleep quality," Giovanni says. Make sure your body has the nutrients it needs to produce serotonin to help get better sleep; you can try one of these tricks for a better night's rest, as well.
You're always hungry
It's normal to feel hungry again three to four hours after a full meal. But if you find yourself feeling hungry again shortly after eating, you may need to add more protein to your meals. "Protein increases your feelings of fullness because it takes longer to break down than other macronutrients," says Caleb Backe, personal trainer and health expert for Maple Holistics. "This means that protein is in your system for longer, keeping you full and evening out your blood sugar levels."
You're feeling fatigued
If you're feeling sluggish and tired and you aren't sure why, you may want to take a look at what's missing from your diet. A deficiency in nearly any important nutrient can result in fatigue - including protein. "If someone starts feeling consistently more tired, that's an indication that they're not getting all the nutrition that they need," says Kari Leland, registered dietitian at Georgetown University Hospital. "They may not be eating enough or, if they have a lack of protein over an extended period of time, it could lead to anemia." A side effect of anemia is often fatigue.
You have fatty liver disease
If you have fatty liver disease, you may have more to worry about than missing out on protein. But, for reasons that are still unclear, the condition is associated with a deficiency in protein. "Why it occurs in cases of protein deficiency is unclear, but studies suggest that an impaired synthesis of fat-transporting proteins, known as lipoproteins, may contribute to the condition," says nutritionist Vanessa Rissetto.
You're having trouble concentrating
If you're having trouble staying focused at work or find yourself feeling scatterbrained and foggy, it could be linked to a deficiency in your diet. "Protein and carbohydrates together create certain neurotransmitters that help us focus and concentrate," explains Giovanni. "When we are missing one of these vital nutrients, that process doesn't work as effectively." However, Giovanni notes that this lack of focus could also come from a lack of food overall. "Not eating enough can also make it difficult to concentrate," she says. "Glucose (found mostly in foods that contain carbohydrates) is the brain's only source of fuel; without it, your brain will not function optimally."
You have a higher risk of bone fracture
"Protein helps maintain the strength and density of bones," Rissetto explains. "Insufficient protein intake has been linked to a lower bone mineral density and an increased risk of fractures." Calcium isn't the only nutrient you need to maintain bone health. These other foods can also help ensure you keep your bones strong and healthy.
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