Many of us start off the year with a determination—backed by a gym membership—
to get into shape and lose weight. It now is February.
How are those New Year's resolutions faring? Is it time for Plan B?
If that means diets and weight loss aids, there is no one-size-fits-
all. Choosing the right approach with realistic expectations
as to how much can be lost and how quickly will help prevent
frustration and disappointment, not to mention major weight
regain later in the year. Research in advance is the key. The
following are some major categories and rationales for weight
- Appetite suppressants and mood enhancers
- Calorie (carbohydrate and/or fat) absorption blockers
- Diuretics and laxatives
- Metabolism enhancers and thermogenic agents
- Nutrient partitioning agents
Of the above approaches, for many reasons, the most commonly
adopted method remains that of metabolism enhancers and
thermogenic agents. Typical ingredients for this tactic for weight
loss are bitter orange, caffeine, country mallow, green tea,
guarana, 7-keto DHEA, synephrine, yerba mate and yohimbe.
Inasmuch as one or more of these ingredients can lead to side
effects if used incorrectly or by individuals for whom they are
inappropriate, the following observations start by examining
How Do Thermogenic Agents Function Within the Body To Burn Fat?
Thermogenesis literally means causing the production of
heat. Aside from the shivering response to cold, body heat
production is a side effect of exercise and or of increased basal
metabolic rate. The thermic effect of food ideally should be on
the order of 10 percent of calories consumed. Thermogenic
products are designed to stimulate the metabolism to be
above where it normally would be in order to burn additional
calories and to access fatty acids for this purpose. The most
common approach for achieving this is to manipulate one of
the body's hormonal signals, usually norepinephrine. Green
tea epigallocatechin gallate (EGCG) reduces norepinephrine
degradation and thereby increases catecholamine-mediated
stimulation of β-adrenergic receptors and activates the
sympathetic side of the nervous system. Ingesting EGCG by
itself and in conjunction with caffeine prolongs the actions
of norepinephrine. This increases the metabolic rate, hence
increases energy expenditure by increasing the oxidation of
glucose and fat for energy and increasing calorie-consuming
actions. As a rule, there is a significantly greater mobilization
and utilization of fat for energy than glucose—in fact, most
metabolic stimulants cause fat to be released from storage
so that it is more readily available for energy generation. The
stimulation involved may make a person more wide awake and
even more inclined to exercise, but some of the stimulation may
involve what are termed "futile cycles" that consume energy
and create heat, but do not lead to physical exertion.
How Can Those Who Want To Avoid the Negative Effects of Stimulants Benefit From Thermogenic Agents?
There are at least three side effects that dieters should look to
avoid: 1) increased heart rate, 2) increased blood pressure and
3) excessive central nervous system stimulation. One solution
to the cardiovascular side of things is to improve the circulation,
especially to the heart. Hawthorne extracts help to open the
circulation of the coronary artery, that is, the main blood supply
to the heart. Herbs such as specialized grape seed extract and
wild bitter melon, similarly, are useful for supporting the body in
blood pressure regulation. The mineral magnesium is another
aid here in that it both helps to regulate blood pressure and is
calming to the nervous system.
Excessive stimulation that overly activates the central
nervous system leading to agitation, emotional control issues
and/or sleeplessness actually does not usually increase
thermogenesis, a fact that emerged from the ephedra-caffeine
trials at Harvard and elsewhere. The clearly thermogenic
combination of ephedra-caffeine increased energy expenditure
at low to moderate doses, but above a not particularly high level
of intake the amount of extra calories burned went down rather
than up. Moreover, excessive stimulation induces a release of
cortisol, which tends to cause the loss of lean tissue rather than
For Consumers Who Use Caffeine To Increase Their Metabolism,
What Are the Concerns Surrounding Caffeine?
Caffeine definitely is a mixed bag when it comes to metabolism.
- Looking only at caffeine by itself, there is evidence for acute increases in resting metabolic rate and thermogenesis, but habituation nullifies such benefits with chronic intake.
- Habitual caffeine use reduces the benefits of caffeine/EGCG mixtures compared to findings in test subjects who do not consume significant amounts of caffeine regularly.
- Overall, there is little or no support for the claim that caffeine by itself induces or maintains weight loss over the long term.
In short, caffeine is more useful for metabolic effect if
consumed with something like EGCG, such as from green tea,
but habituation is rapid. Caffeine-related compounds in green
mate appear to have more benefits over the long term than does simple caffeine. The health benefits of coffee, such as they
are, come from chlorogenic acid and related compounds, not
mainly from the caffeine.
Keep in mind, an intake of 700 mg or more caffeine per day
(about five cups of coffee) is often associated with depression
and mood swings. Some authorities draw the line at 600 mg
per day. Caffeine causes short-term increases in blood sugar
levels that can be followed by dramatic downward fluctuations.
Consuming caffeine, in other words, is yet another path to
the sugar "roller-coaster" of energy ups and downs and sugar
cravings. Cutting out caffeine and refined sugars for as little as
one week has been shown clinically to improve mood in many
individuals complaining of depression.1
What Are Some of the Concerns Surrounding Weight Loss Supplements, Such as Synephrine and Yohimbe?
No doubt, the major concerns are elevated blood pressure and
elevated heart rate. In addressing these concerns, the source of
synephrine is important. ρ-synephrine is an alkaloid occurring
naturally in some plants and animals. A related compound is
found in approved drugs as the m-substituted analog known as
neo-synephrine. Bitter orange (Citrus aurantium) is a source of
ρ-synephrine, which does not seem to increase blood pressure
significantly, although it may have an effect on heart rate. (http://www.medsci.org/v09p0527.htm) m-Synephrine, often confused in the literature with ρ-synephrine, exhibits cardiovascular
effects, but reportedly is not a constituent of bitter orange. It
remains controversial whether ρ-synephrine exerts effects on
blood pressure and heart rate if consumed with large amounts
of caffeine or other stimulants.
ρ-Synephrine is used to increase energy expenditure and
lipolysis; ρ-synephrine is a β-3 adrenergic receptor agonist,
which is to say, a thermogenic compound. By itself, ρ-synephrine
as found in bitter orange is not associated with significantly
increased blood pressure or heart rate; no significant
α-adrenergic effects have been demonstrated, unlike the case
with, say, ephedrine.2 Again, synthetic synephrine is a slightly
different compound and can lead to high blood pressure and
other effects even at relatively modest doses.
It is neither necessary nor useful to push an intake of
ρ-synephrine above approximately 50 mg. Rather, greater energy
expenditure is induced by adding 600 mg naringenin to the
mixture and a further increase can be induced by adding 100 mg
Another widely promoted thermogenic herb is yohimbe
(Pausinystalia yohimbe). It is claimed as a thermogenic agent due
to its active component, yohimbine, an α-2 receptor antagonist.
Three double-blind RCTs, which included patients who were
> 15–20 percent over their ideal body weight or had a BMI
ranging between 28 and 48 and lasted three weeks to six
months, yielded weight loss only at three weeks on a restricted
diet, the loss being 1.34 kg greater than with placebo.3 However,
yohimbe exhibits erratic effects on blood pressure, heart rate
and neurological parameters with a high risk of toxicity.4
How Do the Satiety Supplements 5-HTP and Hydroxycitric Acid Work?
Items that affect serotonin, such as 5-HTP
(5-hydroxytryptophan) and St. John's Wort, may influence
mostly carbohydrate consumption. 5-HTP activates
serotogenic pathways and at 600 to 900 mg/day induces
weight loss of 3.1–3.7 pounds in 5–6 weeks without dieting.
At 900 mg, 70 percent of subjects experienced significant
nausea, but adjusted after six weeks.5 Although anyone being
treated with pharmaceutical psychoactive drugs should not use
5-HTP without their doctor's agreement, 5-HTP otherwise has
been found to be safe at ordinary dosages.6
(–)-Hydroxycitric Acid / HCA, always sold as a mineral salt,
is unusually well studied with at least 12 randomized placebo-controlled
trials, but studies have used different salts and widely
differing dosages. Mechanisms of action remain controversial.
HCA does not cross the blood-brain barrier, hence does not
influence the central nervous system directly; neither does it
depend on activating nerves involving the liver (vagal afferents).
HCA delays gastric emptying, however, and it prolongs glucose
absorption from the small intestine. The primary effects seem
to be to reduce between-meal snacking and to increase the
length of time that dieters feel satiated after meals. Potassium
and potassium-magnesium HCA salts are insulin sensitizing
at human acceptable dosages whereas calcium- and calcium-potassium
HCA salts are not. Apparently no one has tested the socalled
"triple" salts even in animals. Weight loss in randomized
controlled trials (RCTs) ranges from none to approximately 1/2
to one pound per week for eight weeks at higher dosages (2.8 g
HCA) of potassium-based salts. In other words, approximately
4.5 grams/day of a potassium-based salt can lead to as much
as one pound per week weight loss if taken as directed. Weight
loss normally starts after the first or second week of usage for
reasons having to do with refilling glycogen stores in the liver
and muscle as well as greater hydration of muscle tissue. No
toxicity or significant side effects have been found with properly
manufactured HCA salts in controlled trials and safety reviews.
Despite extremely widespread usage for roughly 25 years, only
a handful of adverse event reports have appeared, usually with
combination products and/or in cases in which the report could
not even name the HCA salt involved.7,8
Do Chia Seeds and Similar Foods Promote Satiety?
Good fiber sources, especially very viscous fibers, increase
satiety by increasing stomach distention (the feeling that
the stomach is extended and full) and reducing the rate of
gastric emptying. They also tend to reduce the rate at which
carbohydrates release glucose into the blood stream. Viscous
soluble fibers include, but are not limited to pectins, β-glucans,
psyllium, glucomannan and guar gum. Foods such as ground
flax seed, baked acorn squash, artichoke hearts and most
legumes are good fiber sources. Oats and barley are good
items, but not if they have been "instantized" since this process
causes them to act more like high-glycemic foods.
Protein sources also are good for satiety, although one can over-consume calories from protein just like anything else.
Plant protein sources are slower to be absorbed into the tissues
and thus may be especially good for prolonging satiety.
At the other end of the scale, fructose is a particularly
bad sugar for dieters and for health in general. Indeed, it is
significantly worse than glucose or sucrose according to recent
How Do Fat and Carbohydrate Blockers Aid in Weight Management?
White kidney bean extracts and a number of other products,
including bitter melon, inhibit carbohydrate digestion by
inhibiting the actions of alpha-amylase and/or related
compounds. The drawback of these in the American diet is that
more and more calories in our diet are from corn sugar and
other simple sugars. Indeed, corn sugars often are the cheapest
binders and fillers available for processed foods. Carb blockers
may be helpful with traditional foodstuffs, but this is modern
America. Corn is subsidized and processed corn components
HCA reduces the rate at which carbohydrates are available,
but it is not a traditional carbohydrate blocker. Its mechanism
of action is different in that it slows and prolongs the passage of
glucose across the gut membrane into the blood stream via its
effects on the sodium pump in the gut. There likely are a small
number of other supplements that work similarly.
A well-known lipase inhibitor (blocker of fat digestion) is
derived from Cassia Nomame Mimosoides. This item was created
to mimic the actions of a pharmaceutical weight loss product
that inhibits the absorption of 30 percent of fat found in the
diet. Concerns are sometimes expressed as to the wisdom on
preventing the proper digestion of fats in the small intestine.
Unlike carbohydrates, which can be acted upon by various
bacteria in the large intestine, the body is poorly equipped to
chronically handle fats not digested in the normal fashion. At
this point in time, even the pharmaceutical fat blockers have
largely disappeared and no trials seem ever to have been
undertaken to demonstrate the efficacy of "natural" fat blockers
claimed to be natural alternatives to the drugs.
Begin with Your Eating and Exercise Habits
To repeat a point made in articles in the past, diets that are
inadequate in terms of vitamins and minerals, and in many
cases protein, often coincide not only with weight gain, but
also with low energy levels and mood swings. The consumption
of a diet based largely upon sugars, refined carbohydrates,
soft drinks and "junk foods" in general is just not sufficient to
maintain good bodily health. If the overall quality of health is
poor, it is unlikely that mental functioning and emotional well-being
will fare any better. A powerful incentive for binge eating
and a source of sugar cravings is the effort to counter depression
and mood swings.
Remember, as well, the place of exercise. Exercise is less
important for its role in directly burning calories than for
increasing basal metabolic rate in the morning and helping
the body to access fats for energy. As little as 20 to 30 minutes
walking every day can help the body to relearn how to burn
fat for fuel. Walking early in the day has the added benefit of
speeding up the metabolism when this can do the most good
and also providing a daily dose of mood-brightening sunshine.
Before or after the evening meal are two other good times to
take a walk.
- Kreitsch, K., et al. Prevalence, presenting symptoms, and psychological characteristics of individuals experiencing dietrelated mood disturbances, Behav Ther 1988;19:593–604.
- Stohs SJ. Safety, Efficacy, and Mechanistic Studies Regarding Citrus aurantium (Bitter Orange) Extract and ρ-synephrine. Phytother Res. 2017 Oct;31(10):1463–74.
- Pittler MH, Ernst E. Dietary supplements for body-weight reduction: a systematic review. Am J Clin Nutr. 2004 Apr;79(4):529–36.
- Woolf AD, Watson WA, Smolinske S, Litovitz T. The severity of toxic reactions to ephedra: comparisons to other botanical products and national trends from 1993–2002. Clin Toxicol (Phila). 2005;43(5):347–55.
- Cangiano C, Ceci F, Cascino A, Del Ben M, Laviano A, Muscaritoli M, Antonucci F, Rossi-Fanelli F. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. Am J Clin Nutr. 1992 Nov;56(5):863–7.
- Das YT, Bagchi M, Bagchi D, Preuss HG. Safety of 5-hydroxy-L-tryptophan. Toxicol Lett. 2004 Apr 15;150(1):111–22.
- Chuah LO, Yeap SK, Ho WY, Beh BK, Alitheen NB. In vitro and in vivo toxicity of garcinia or hydroxycitric acid: a review. Evid Based Complement Alternat Med. 2012;2012:197920.
- Márquez F, Babio N, Bulló M, Salas-Salvadó J. Evaluation of the safety and efficacy of hydroxycitric acid or Garcinia cambogia extracts in humans. Crit Rev Food Sci Nutr. 2012;52(7):585–94