process of DNL is determined by the activity of an enzyme called ATP lyase, which HCA may
inhibit. Additionally, it may enhance fat utilization and blunt appetite (13,14). Some authors
have suggested that HCA will have similar effects in humans and may have a role in fat loss and
exercise performance (15-17).
The problem with HCA is the lack of human research to show its effectiveness. The
biggest argument against HCA is that DNL is not active in humans under normal conditions
(18). As discussed in chapter 12, DNL can occur under one specific situation: severe
carbohydrate overfeeding, as might occur during the carb-up phase of a CKD (19).
Although no research exists on this topic, anecdotal evidence suggests that the use of HCA
can improve the carb-up, giving better muscle glycogen resynthesis with less spillover of water
and fat. Additionally, in some people HCA blunts appetite, which may be good or bad during a
carb-up. For those individuals who tend to over consume calories during a carb-up, HCA may be
of benefit. For those individuals who find it difficult to consume sufficient carb calories during the
carb-up, HCA may not be a good supplement to try.
The typical dose of HCA is 750-1000 mg of active ingredient taken three times per day.
Since HCA comes in 50% standardization in most products, this means that 1500-2000 mg will
need to be taken. An important aspect of making HCA effective is that it must be in the liver
prior to the consumption of carbohydrates. This generally means that HCA should be taken at
least thirty minutes before a meal is consumed.
Finally, in some individuals HCA seems to inhibit ketosis during the week although the
exact mechanism is unknown. Beyond a potential effect on ketosis, as no carbohydrates are
being consumed during the low-carbohydrate week of a CKD, HCA is unnecessary. Some
products containing the ECA stack include HCA in them. These products are inappropriate for
use during the lowcarb week.
Section 3: Supplements that increase
glycogen storageThe final mechanism by which supplements may improve the carb-load is by increasing
glycogen storage. The two major supplements which may increase glycogen storage during the
carb-load are creatine and glutamine. Both are discussed in greater detail in the next chapter.
Glutamine is an amino acid which has been found to increase glycogen storage when
consumed with carbohydrates (20). Additionally, creatine has also been found to increase
glycogen synthesis when taken with carbohydrates (21). Therefore individuals may wish to
experiment with one or both during the carb-load phase, to see if it gives them noticeably better
glycogen supercompensation. As mentioned in the next chapter, glutamine supplementation can
keep some people out of ketosis. If individuals find it difficult to establish ketosis after having
used glutamine during the previous carb-load, they should try carb-loading without the glutamine
to see if there is any difference.
References cited