Does Cholesterol Really Causes Heart Attacks? — Transcript

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1. 0:00there is no such thing as bad or good
2. 0:02cholesterol today we're debunking myths
3. 0:04and going through what you need to do to
4. 0:06protect your heart cholesterol is a waxy
5. 0:09fat-like substance that's found in all
6. 0:11cells in the body your body needs this
7. 0:13cholesterol to make hormones vitamin D
8. 0:15and help to digest your foods but
9. 0:17there's a problem cholesterol doesn't
10. 0:19mix with blood think of trying to mix
11. 0:21oil and water it doesn't work and they
12. 0:24separate out instead the cholesterol is
13. 0:26packaged up into Vehicles called
14. 0:28lipoproteins so LDL or lowdensity
15. 0:31lipoprotein simply refers to the density
16. 0:34of the cholesterol that's packaged into
17. 0:36that lipoprotein the cholesterol
18. 0:38structure itself is exactly the same
19. 0:40whether it's transported in a high
20. 0:41density lipoprotein or a low density
21. 0:44lipoprotein the cholesterol itself
22. 0:46doesn't cause heart disease instead it's
23. 0:49the concentration of the cholesterol
24. 0:50carrying lipoproteins in the blood that
25. 0:52really matter and here comes the yelling
26. 0:55from the keto and carnivore influencers
27. 0:57who will say things like cholesterol
28. 0:58carrying lipoproteins don't matter what
29. 1:01matters is insulin resistance and your
30. 1:03overall metabolic Health they'll bring
31. 1:05up graphs like this one showing that low
32. 1:07low density lipoprotein levels are
33. 1:09associated with higher death rates and
34. 1:11the ideal LDL cholesterol level is 140
35. 1:15mg per dcil now the stakes are high we
36. 1:18absolutely need to get this right so
37. 1:20that we can prevent heart attacks and
38. 1:21strokes this is not to be trifled with
39. 1:24so let's unpack this myth step by step
40. 1:27firstly this is an observational study
41. 1:29so all the authors did was simply
42. 1:31observe the population to see what
43. 1:33Trends they could see but correlation
44. 1:35doesn't equal causation instead what's
45. 1:38happening is that these low levels of
46. 1:39LDL cholesterol are largely a marker of
47. 1:42severe disease essentially when a
48. 1:45population is observed those who have
49. 1:46got chronic diseases such as cancer or
50. 1:49chronic kidney disease they often have
51. 1:51low levels of LDL cholesterol instead we
52. 1:53know that when we actively intervene and
53. 1:55lower a person's LDL cholesterol levels
54. 1:58we lower the rates of high heart disease
55. 2:00and we know this from randomized control
56. 2:03trials q more yelling from the keto and
57. 2:05carnivore influencers who will say that
58. 2:07those results are explained by reduced
59. 2:09inflammation levels that when we
60. 2:11actively lower a person's LDL
61. 2:12cholesterol levels we're also lowering
62. 2:14their inflammation and it's the lower
63. 2:16inflammation levels that are responsible
64. 2:18for the lower cardiovascular disease
65. 2:20it's got nothing to do with the LDL
66. 2:22cholesterol levels so let's address that
67. 2:24point we have a massive trial called the
68. 2:27pza study PESA and enrolled over 4,000
69. 2:31individuals who underwent three-yearly
70. 2:33examinations looking for blockages in
71. 2:35their blood vessels what they found is
72. 2:37that for people that had optimal values
73. 2:39for their cardiovascular risk factors so
74. 2:42they were insulin sensitive they were at
75. 2:43the perfect weight that had low levels
76. 2:45of inflammation there was still a
77. 2:47significant correlation between LDL
78. 2:49cholesterol levels and the presence of
79. 2:51blockages in blood vessels and we can
80. 2:53see this quite clearly on the graph
81. 2:55where as the lzl cholesterol levels
82. 2:57increase so too does the chance of
83. 2:59developing blockages in our blood
84. 3:01vessels again what this trial tells us
85. 3:03is even if you don't have insulin
86. 3:05resistance if you have low levels of
87. 3:07inflammation and you are a perfect
88. 3:09weight you can still develop blockages
89. 3:11in your blood vessels if the
90. 3:12concentration of the cholesterol
91. 3:14carrying lipoproteins is high enough and
92. 3:16when you lower that concentration as
93. 3:18evidenced by the randomized control
94. 3:20trials you lower your chance of
95. 3:22blockages in your blood vessels you
96. 3:24lower the chance of heart attacks and
97. 3:26strokes now one criticism of the piece
98. 3:28of study is that in the very low LDL
99. 3:30cholesterol group there was only two
100. 3:32participants this is because without
101. 3:34using medications it's almost impossible
102. 3:37to reach these low levels of LDL
103. 3:39cholesterol you have to have won the
104. 3:41genetic lottery so it's very rare to
105. 3:43have LDL cholesterol levels this low
106. 3:46however as the numbers of participants
107. 3:48increase again you can quite clearly see
108. 3:50the trend where as LDL cholesterol
109. 3:52levels increase so too do the chances of
110. 3:54developing blockages in our blood
111. 3:56vessels and taken together this supports
112. 3:58the idea that the lower your LDL
113. 4:00cholesterol levels are the better as in
114. 4:03the more protected you are against heart
115. 4:05attacks and strokes so how does a high
116. 4:07concentration of lowdensity lipoprotein
117. 4:09particles cause blockages in our blood
118. 4:12vessels like I mentioned earlier
119. 4:14correlation doesn't equal causation we
120. 4:16need to have a firm mechanism for how
121. 4:18LDL particles can cause blockages in our
122. 4:21blood vessels and this was explained
123. 4:23beautifully by the European
124. 4:24atherosclerosis Society they explain
125. 4:27that LDL particles they don't just
126. 4:29passively move across blood vessel walls
127. 4:32instead there are specific Pathways to
128. 4:34cross the blood vessel walls and this is
129. 4:36called trans cytosis the take-home
130. 4:39message before we move on to the next
131. 4:40point is that if the LDL particles reach
132. 4:43a certain concentration even if you are
133. 4:45metabolically healthy you are insulin
134. 4:47sensitive and you've got a perfect
135. 4:48weight you can still develop blockages
136. 4:50in your blood vessels and it's not the
137. 4:53cholesterol itself it's the
138. 4:54concentration of the cholesterol
139. 4:56carrying lipoproteins that really
140. 4:58matters but lipo protein concentration
141. 5:00isn't the only factor that we need to
142. 5:02worry about we still have to address all
143. 5:04of the other risk factors including
144. 5:06insulin resistance blood sugar levels
145. 5:09inflammation blood pressure weight all
146. 5:11of those risk factors including
147. 5:13lipoprotein concentrations need to be
148. 5:15addressed to reduce our chance of heart
149. 5:17attacks so coming back to lipoproteins
150. 5:20which lipoproteins do we need to worry
151. 5:21about because on a regular lipid blood
152. 5:24panel you'll see lzl cholesterol that's
153. 5:27a measure of the amount of cholesterol
154. 5:28that the L l l particles are carrying it
155. 5:31doesn't actually measure the number or
156. 5:33concentration of the LDL particles and
157. 5:36it's not just LDL particles that
158. 5:38contribute to blockages in our blood
159. 5:39vessels there are different types of LDL
160. 5:42particles such as small dense LDL
161. 5:44oxidized LDL and there's lipoprotein
162. 5:47little a just to name a few so just
163. 5:49relying on LDL cholesterol is an
164. 5:52incomplete marker ideally if my patients
165. 5:54have the resources to fund it I
166. 5:56encourage them to check their EPO levels
167. 5:59aob is a primary protein component of
168. 6:01lipoproteins that cause issues with
169. 6:03respect to our blood vessels it's the
170. 6:05Appo family of lipoproteins that can be
171. 6:08retained in our blood vessel walls again
172. 6:10leading to blockages you'll hear some
173. 6:12people talking about oxidized LDL or
174. 6:15small dense LDL that those are the ones
175. 6:18to worry about that has been debunked
176. 6:20it's the concentration of the epob
177. 6:22containing lipoproteins that really
178. 6:24matters and for my patients that I see
179. 6:26at the clinic we aim for epob levels
180. 6:28below 60 mg per dcil but as mentioned
181. 6:31earlier there are costs involved in
182. 6:33measuring your Appo levels so if we have
183. 6:36to rely on LDL cholesterol levels alone
184. 6:38we still Target a level below 60 mg per
185. 6:41dcil now you'll notice that that level
186. 6:44is significantly less compared to the
187. 6:46American Heart Association guidelines
188. 6:48and I'll reference the pie of study
189. 6:50again because we can see that if the LDL
190. 6:52cholesterol levels are above 60 that's
191. 6:55when it seems that aerosis or blockages
192. 6:57in our blood vessels can occur the next
193. 6:59question is why don't we pay that much
194. 7:01attention to the HDL cholesterol levels
195. 7:04that are also commonly measured on a
196. 7:06standard lipid blood test it used to be
197. 7:08thought that by raising the
198. 7:09concentration of HDL particles we could
199. 7:12be protected against heart disease
200. 7:14unfortunately those studies failed and
201. 7:16that's why clinicians instead focus on
202. 7:18apob levels so how do we lower Appo
203. 7:21containing lipoproteins well we always
204. 7:24start with diet and we don't just want
205. 7:26to focus on a diet that lowers epob
206. 7:28levels ideally we want a diet that also
207. 7:30helps to lower blood pressure and lower
208. 7:32our weight so to provide a quick summary
209. 7:35we want a whole food high protein diet
210. 7:37but the proteins that we select should
211. 7:39be lean as in low saturated fat we know
212. 7:42from a Cochran review that as we lower
213. 7:44our saturated fat intake we lower the
214. 7:47chance of heart attacks and a quick note
215. 7:49that saturated fat is different to
216. 7:51dietary cholesterol so for most patients
217. 7:53dietary cholesterol that's commonly
218. 7:55found in things like eggs doesn't have a
219. 7:57huge impact on our blood cholesterol
220. 7:59levels it's the saturated fat that
221. 8:01increases our blood lipoprotein
222. 8:03concentrations we also want to focus on
223. 8:06high fiber foods because again from
224. 8:08Cochran we can see that as we increase
225. 8:10our fiber intake we lower our total and
226. 8:13LDL cholesterol levels and in terms of
227. 8:16blood pressure we want to be consuming
228. 8:17high potassium foods such as beans
229. 8:20lentils avocados spinach broccoli and
230. 8:23peas and of course we want to be
231. 8:25exercising now if diet and exercise
232. 8:27Aren't Enough there are a myriad of
233. 8:29cholesterol lowering medications that we
234. 8:30can use so make sure to check out this
235. 8:32next video here on the medication that I
236. 8:34use in addition to diet and exercise to
237. 8:37lower my cholesterol levels