In the vast landscape of dietary supplements, it can be challenging to separate the truly effective and safe ones from the overhyped. With promises of improved health and longevity, how can you discern which supplements are backed by science and which are merely trendy fads? Here, we discuss supplements that are supported by strong scientific evidence.
Creatine is a compound formed from the amino acids L-arginine, glycine, and L-methionine. It plays a crucial role in energy metabolism, muscle performance, and recovery. Creatine can also be used to increase high-intensity exercise capacity and lean body mass (rather than fat mass) during training. Initial safety concerns regarding creatine have been disproven. Studies have found that creatine does not cause hair loss or increased uric acid levels, does not result in kidney damage in healthy people, and is not associated with either dehydration or muscle cramping.
Emerging evidence suggests that creatine supplementation increases both muscle and brain creatine stores. This is particularly important during periods of stress—such as sleep disruption and aging—which cause reductions in brain creatine levels. A 2022 meta-analysis (a study that combines the results of multiple studies) showed that creatine supplementation can enhance memory performance in healthy individuals, especially in older adults (66–76 years).
Creatine is usually dosed at 5 mg per day in the form of Creatine Monohydrate. Powders tend to dissolve poorly in cold and room-temperature water, so they need to be mixed with warm water.
Higher muscle strength is associated with lower death rates from all causes, so it is important to maximize muscle strength in youth, maintain that muscle strength in middle age, and minimize muscle loss in older age. Nutrition and exercise training can slow or reverse muscle weakening, functional impairment, and disability, so clinical guidelines suggest increasing our protein intake.
Some studies have reported that mice live longer on a low-protein diet, leading some people to recommend low-protein diets for longevity. However, this has not been shown in humans. We need to preserve muscle strength in order to maintain independence and resilience against disease during aging. Furthermore, a 2020 study reported that higher total protein intakes are associated with lower all-cause death rates, thereby supporting the benefits of the recommended 1.6 - 2.2 g/kg body weight/day of dietary protein. Note that an intake higher than 1.62 g/kg/day does not further contribute to resistance training-induced increases in muscle mass. Older adults should aim for a protein intake of 2 g/kg/day (i.e., 160 g of protein for an 80 kg individual). This higher intake would help older adults compensate for their muscle loss and the fact that their digestive tracts do not absorb protein as well as younger people.
The International Society of Sports Nutrition recommends multiple protein meals throughout the day, spaced 3-4 hours apart. Protein in protein powders is highly bioavailable, and powders—which should ideally not have added salt and sugars—can be mixed in with smoothies and shakes.
TMG helps to accelerate the recycling of adenosine triphosphate (ATP, the cell's energy currency). This could boost muscle protein synthesis and improve performance by staving off fatigue during high-intensity activities.
In a 2017 systematic review, TMG supplementation was shown to increase strength and power only when combined with exercise training. Indeed, TMG might be most effective when combined with high-intensity strength/power exercise, so TMG is likely to work best in a training environment with high metabolic demands. For example, TMG increased VO2max (aerobic fitness) and repeated sprint ability performance in professional youth soccer players. By contrast, TMG supplementation with or without creatine supplementation did not affect strength and power performance in untrained individuals.
Homocysteine is an amino acid that increases the risk of Alzheimer's disease when its levels in the blood are elevated. Therefore, lowering high blood homocysteine levels is one of the most promising interventions to help prevent Alzheimer's disease. TMG reduces the levels of homocysteine in the blood. More research on the effects of TMG on dementia rates is warranted, but given the current knowledge about the benefits, TMG is usually dosed at 500 mg – 1 g per day.
A study reported that 31% of the U.S. population were at risk of at least one vitamin deficiency or anemia. People often struggle to reach the recommended daily intakes of all the micronutrients—especially vitamin B3, vitamin D3, vitamin K2, zinc, and magnesium—from diet alone. A recent large study showed that daily multivitamin-mineral supplementation for three years improved global cognition in older adults. Most multivitamin supplements significantly overshoot recommended daily intakes, but when choosing a multivitamin or mineral supplement, opt for one that avoids 'mega dosing' and is formulated to supplement a healthy diet.
