Obata and colleagues were the first to suggest this developmentally regulated shift at the level of the spinal cord [3]
Hence, the popular fitness trainer wisdom about The more muscle you have, the more calories you burn, even at rest. Unless you strength-train and take other steps to counteract age-related muscle loss, you can expect to lose 4 to 6 pounds of muscle per decade
As an alternative methyl donor, betaine plays a central role in maintaining methylation capacity, and its depletion may contribute to elevations in S-adenosylhomocysteine and impaired methyltransferase activity
Top Sources: Oats, barley, rye, quinoa, apples, berries, bananas, citrus fruits, broccoli, carrots, Brussels sprouts, flaxseeds, chia seeds, and legumes